Random Synapses

So here’s the story. Less than a year ago I bought two identical Dell Latitude C610 laptops. They have been previously used in a corporate environment, looked and worked very well, and offered sufficient portable computing power at a reasonable price (400€ + 19% tax). Adding Intel ProWireless miniPCI cards for 802.11b/g WiFi connectivity to the Intel Pentium III Mobile processors transformed them into Centrinos. And I was happy.

Until one of the hard drives died.

Both laptops were using 2.5″ IDE Hitachi hard drives with 12 and 20 GB respectively at 4200 rpm. They were slightly noisy and slow. Hitachi is an important player on the hard drive market, they even took over IBM’s hard drive production line. Their desktop drives are pretty good, but they have a history with poor laptop drives. I feared the day when the laptops’ drives will eventually fail, but I didn’t expect that day to come so soon. After a few days of fiddling with the faulty drive trying to recover some useful data off it and resurrect it with Hitachi’s diagnostic tools and finally with HDD Regenerator when nothing else worked, the drive finally became suffocated with bad sectors and could no longer be used, displaying a “Bad Drive” message at boot-up through S.M.A.R.T..

With the laptop still under warranty, the hard drive was replaced free of charge… with another Hitachi. And the new one made a high-pitched hiss sound all the time. Fearing another failure, I decided to shop around for replacement drives with faster access, bigger space and higher reliability. 4200 rpm drives are pretty much old technology, with the new 5400 rpm drives using state of the art motors; a 5400 rpm drive will not only perform slightly faster than a 4200 rpm drive, but should also reduce noise, heat and power consumption. I was searching for a “best buy” in terms of performance over cost and also keeping reliability as a key element in the equation. With Samsung, Toshiba, Seagate and Western Digital lining up their 2.5″ hard drive models under my nose, I started comparing performance, reliability and price. What I did was to compare price/gigabyte for similar drives, for example finding the prices for the 60 GB, 5400 rpm, 2 MB cache drives, then dividing the price by 60 to find out how much I was paying for one gigabyte in each model. Similarily, I compared the 40, 60, 80 and 100 GB variants of the same line from each manufacturer, to find out which drive size provided the lowest cost.

The best cost/size turned out to be an 80 GB drive with 8 MB of cache. I had to rule out Toshibas for their insane prices over here, and Samsung for getting a mixed bag of reviews online. The two competitors left in the race were the Western Digital Scorpio and the Seagate Momentus 80 GB models. Having read many, many reviews online, including Tom’s Hardware’s Nine Notebook Hard Drives Make Their Debuts as well as forum discussions and buyers’ opinions, I picked the Western Digital Scorpio. It was also slightly cheaper than the Seagate, and it was also reported to perform slightly faster than the similar Momentus.

So here I was, with two identical laptops and two identical Western Digital hard drives, all excited about the huge portable storage space and performance. But my excitement turned to a two month long nightmare, when I discovered that both hard drives made a repetitive clicking sound every 2 seconds, making one of the laptops freeze up. The noise itself was not a problem, it was hardly audible, but it was making the computer freeze momentarily, even interrupting something as simple as displaying a menu. Diagnosing the problem was difficult since the clicking was an intermittent problem and I suspected the laptops to be faulty. After several tests, it became clear that both hard drives were having problems in one of the laptops and only one was clicking in the other laptop. Curiously enough, Western Digital’s excellent diagnostic utility could not find anything faulty with the drive, no physical errors, no S.M.A.R.T. failures. DiskMon from SysInternals.com did not find any relevant information regarding Windows’ accessing the drive repeatedly to cause the clicking. The noise did not occur when the hard drive was under heavy load, but when idling and having to read or write small amounts of data. I have tried everything, from installing several operating systems and updating drivers to changing power management settings and drive’s performance settings (maximum performance, maximum power saving or automatic). I even re-updated the laptops’ BIOS with the most recent version provided by Dell.

Nothing worked.

Then, in a moment of inspiration, I searched Dell’s downloads for Western Digital Scorpio. Surprise! Western Digital knew about the clicking sound of its Scorpio hard drives in Dell laptops and quietly provided Dell users with a firmware update for the hard drives of specific models to fix the problem. Dell didn’t list the update in older laptop models’ (like Latitude) lists of available downloads, but only in those models which had the Western Digital Scorpio drives as an original purchase option (the Inspiron series). The new firmware was not published on Western Digital’s website. I read the instructions closely and applied the firmware on both drives holding fingers crossed. (On Dell’s download site, this firmware update is named R99039, enter it in the search field.)

Success!! Well, partial success, at least. The hard drive that had problems with only one laptop was now working fine in both laptops without any clicking (apart from the occasional clicking caused by thermal recalibration, all hard drives do that). But the other hard drive was stubborned and continue to click.

Having no other ideas to solve the problem, I sent a question to a Western Digital technician through their Ask WD A Question customer support option. The answer came back promptly, telling me that the clicking noise is a known problem, the drive is deffective and needs to be sent back to be replaced. The drive went back through the national distribution chain to one of the importers, which held it for tests for 5 long weeks. I was really angry when they sent it back with the diagnostic “the drive is fine,” ignoring my detailed description of the intermittent problem and WD’s e-mail instructing to have the drive replaced, not repaired or tested. I was about to give them a call and escalate this problem to the European WD headquarters, when I thought I should run another search on Dell’s support site…

Surprise #2! A newer firmware update for the Western Digital Scorpio was quietly released for the same clicking problem, with the name R107305. I downloaded the update and installed the firmware on the faulty hard drive, keeping fingers and toes crossed, and…

IT WORKED!!! The clicking is gone. All operating systems perform flawlessly. The hard drive can now shine. The laptop is a joy to use. I’m happy.

Lessons learned? Don’t expect manufacturers and integrators to announce their faults; be on a constant lookout for updates, patches, announcements, drivers, firmwares for older equipment that can perform better. Don’t expect resellers to replace a drive without a fight, especially in “emerging markets” like Romania where customers’ rights are laughed at. When you run into a problem, take a step by step approach at finding the fault; be thorough, be open-minded and document everything you do.

Note for Dell users: There have been many reports on the Dell Forums regarding clicking noises from various hard drives in Dell laptops. In the wide variety of hardware available on the market, there is no such thing as perfect compatibility, and any two components that are supposed to work together may display all sorts of strange, unexpected problems. I was lucky to discover that Western Digital looks into such compatibility problems and offers fixes for them. Other companies might not do that, or might not be interested in supporting older models. Research thoroughly your hardware upgrades and take every piece of information with a grain of salt, including my own conclusions above — everyone is more or less biased.

As I’m on a constant fight with dust in this dirty city, my PC needs a good cleaning every couple of months. Today I decided that it was time to give it a thorough cleaning, since the fans were roaring inside — a clear indication that dust has built up on them. As usual, I was performing a quick visual inspection on the motherboard before putting everything together again, when something caught my attention: one of the large capacitors near the processor looked a little different. Its aluminum cap, normally flat, was bulging out and was covered in some orange foam.

Ut oh, this is bad. In time, electrolytic capacitors slowly turn defective because of the heat, and one sign of this malfunction is the swelling on top, losing electrolyte which corrodes the aluminum (the foamish-like stuff) or even exploding. On a computer motherboard, these capacitors are critical components for the voltage regulators that provide the processors with over 100 watts of power, heating up even to 120 degrees Celsius in the process. If the capacitors fail, then the voltage regulators will not supply the processor with the correct voltages, and the processor, motherboard, memory and even video card will malfunction.

On a side note: the difference between a reputable brand and a no-name manufacturer of motherboard usually consists of the quality of small components such as these capacitors, while the design and important components is almost identical. The no-name manufacturer will use cheaper components that will most certainly fail a lot faster than the quality components used by reputable manufacturers. So, if you decide on a PC Chips or Matsonic or Albatron or MicroStar (MSI) motherboard, saving a few dollars on these cheap brands exposes you to a high risk of the entire system going KABOOOOM. Such situations occur less often with motherboards like Tyan, Gigabyte, Chaintech, Epox, Asus and others. My motherboard is an Epox, but it’s already a few years old — I’m happy it has survived so long without any problems.

Anyway, back to the story. I took out the motherboard and checked all large capacitors closely. Apart from the one losing electrolyte, 3 others were swollen on top. I decided to unsolder all 14 capacitors; among the ones I thought were still good, one was swollen at the bottom! Tomorrow I’m going to an electronic store to buy replacements.

Whew!! I don’t know how long the system would have continued working like this, but it certainly was a matter of months, maybe weeks before the processor burned up from the abnormal voltage and overheating. I feel lucky to have discovered this problem. The new capacitors will cost a total of 2, maybe 3 dollars, but they are critical for making a few hundred dollars worth of technology function properly.

[Later edit] I bought new capacitors for almost $4, soldered them on the motherboard nicely, and I’ll be monitoring voltages and temperatures to see if the board runs at normal parameters. I’m so happy!

Be warned, though; what I have done — messing with the components on the motherboard — is definitely not recommended for the average user! Have your motherboard replaced if it’s still under warranty, but do not try to unsolder and solder components if you are not experienced at this and if you don’t have the proper tools for it (like a temperature-controlled Weller soldering station)! Motherboards and generally computer boards are extremely fine components, with 4 or even 6 layers of circuits and covered with miniatural Surface Mount Devices (SMDs). Applying too much heat or being clumsy at handling the hot iron can destroy the fine circuits or knock off some other components, and there is no fix to those mistakes! Dad’s an electronic engineer and I’ve been playing with circuit boards since I was 4, yet I still kept my fingers crossed when I pushed the Power button after this operation. Don’t try it at home unless you have the experience needed to keep risks to a minimum.

[Two weeks later edit] I finally managed to get hold of the digital camera and take a few photos of the capacitors. Unfortunately, it can’t take macro photos closer than one inch or so, and the detail is not as good as I’d like, but I still hope you can make out the differences.

In the photo below, the two capacitors on the left have their tops swollen; the one on the right is how they should normally look like: flat.

Here are the bottoms of the capacitors. Again, the two on the left clearly have the black rubber caps swollen, while the one on the right appears flat. As they were mounted tightly onto the circuit board, the swelling underneath did not become visible until I removed them from the board. In the photo, all three rest on the flat desk, you can see how the capacitor at the right stands up right while the other two are tilted because they stand on the bulging tops seen in the previous photo.

The original capacitors were green with yellow markings. I have no idea about capacitor manufacturers, and I was only able to find one kind to buy, so that had to work. I bought replacements with exactly the same specifications: capacity, voltage and maximum temperature. My concern was with their size — their diameter, to be exact; new ones had to be of the exact girth or slimmer than the originals, otherwise they wouldn’t fit tightly next to each other on the motherboard. In the photo below, you can see the new capacitor on top, black with white markings, and the original one on the bottom, green with golden markings; they are the same diameter, although the new model is shorter. No problem there.

[Much later edit] The problem I have described above is more frequent than you would imagine. BadCaps.net goes into more detail about the problem and also offers repair services. I guess I have just saved $45 + shipping

Too few people take computer security seriously. One can buy a computer from the supermarket these days. It is no longer regarded as a specialized tool but as a common household device. But nobody told you that you are also the administrator of this powerful device, did they?

Why is security important? Because, if you are reading this, your computer is connected to the Internet. Which means, it is a part of the Internet. Just as you can access other computers (servers) connected to the Internet to use their shared resources (web sites, file servers, e-mail servers and so on), so can others access your computer. So if your computer’s software is insecure, others can exploit those vulnerabilities with various purposes in mind. For example, one could try to access your personal files — things you’d like to keep private, like e-mails and address book, financial reports and credit card information, your medical records, your children’s photos and any sensitive information you have saved on your hard drive. One could try to remotely install programs to give them full access to your computer, thus preparing it to be used in other illegal activities, such as spreading viruses, attacking other computers or websites, or sending millions of spam e-mails.

If such things happen, it’s not the fault of those so-called “hackers”, nor the fault of the producer of your operating system. It’s your computer and your responsibility to manage it. That’s why there’s an “Administrator” or “root” account on your computer. Stop blaming others, it’s not rocket science to secure your computer yourself.

So how does the cat-and-mouse game work? Specialized organizations try to find vulnerabilities in all operating systems, and publish their findings regularily. Since most users use Windows, I’ll focus on it. Every month, new vulnerabilities in Windows’ components are being found, vulnerabilities that can be exploited in certain ways. As soon as such a vulnerability is discovered, Microsoft prepares a “patch” that updates the faulty Windows component; these patches can be downloaded free of charge, and the entire process of discovering newly available updates and installing them is completely automatic through the Internet’s best kept secret: Microsoft’s WindowsUpdate website. On the other hand, “hackers” try to find computers whose administrators didn’t install the patches and which are still vulnerable, and exploit those vulnerabilities to get complete access to that computer.

Let’s make an analogy to make it clearer. Suppose you have a nice barn (your computer) filled with all sorts of goodies (files, resources) for the winter. All your neighbours have similar barns. Everyone is happy with their barns. Once a month, a bunch of city folks with funny hats (security organizations) drive by, and inspect the barns for holes in the walls (software vulnerabilities). Then, they tell about those holes to the builder of all barns (the producer of the operating system) which, in turn, makes plugs to exactly fit each hole (the software patches). These plugs are free and the builder even installs them for free, all you need to do is call them (visit the WindowsUpdate site once a month). Why? Because mice (“hackers”) also learn about those holes in the barns (vulnerabilities), and they will try to get through the known holes to reach the goodies inside (exploit the vulnerabilities). If the barn has all known holes filled with the right plugs, then the mice can’t get in. If one of your neighbours didn’t make the call to the guys with the plugs, his barn will be crawling with squeaking rodents. Get it?

To keep your computer secure, the first step is to elliminate all known vulnerabilities. You do that by visiting the WindowsUpdate website once a month and allowing the site to detect what components need to be updated, to download the patches and install them. Yes, it’s that easy. No, it won’t take forever. Patches released in one month are usually a few megabytes or less, and your computer won’t need all of them; downloading shouldn’t take more than one hour even on a crawling dial-up connection. Is one hour each month too much to spare for the sake of your computer’s security? All you need to remember is to start Internet Explorer and select “Windows Update” from the “Tools” menu once a month. Easy!

If your barn had holes and mice settled in, then apart from plugging the holes you need to eradicate the mice as well. In other words, your operating system’s vulnerabilities are usually exploited by a certain kind of viruses called “worms.” These worms “crawl” through the Internet from one vulnerable computer to another. Once they have found a vulnerable computer, they will infect it and start spreading by finding other vulnerable computers to infect. Preventing the infection is done by patching the vulnerable components, as I have detailed above. But cleaning the worms from your computer is a different task. You could use a commercial antivirus to clean them, but there are free solutions to this problem, too. For example, Symantec, the creator of Norton Antivirus, offers free cleaners for specific viruses. The advantage is that these cleaners are free, are small, and do their job very well. The problem is that you need to know which virus you have in order to get the correct cleaner. This is where Stinger comes in: it is also a free cleaner from McAfee, it’s about one megabyte in size but it knows to detect and remove the most recent and dangerous worms spreading on the Internet — about 50 of them, each with a number of different variants. This is the perfect tool for automagically scanning and cleaning worms in your computer, very simple to use. In other words, Stinger would be the supercat you lock in your barn to find and eat all the mice inside. Is that cool or what?

Enough lecture for today. There’s more to computer security, so make sure you don’t miss the next class. You are one step closer to the rocket scientist diploma you have always dreamed of. Assignment due next time: get Stinger and scan your computer, and install all critical updates for your version of Windows.

It is normal for electronic components to warm up as current passes through. However, they need to be protected from overheating – this is achieved by simple air cooling. Designers came up with the ATX specifications for cases and components, which also takes in consideration the placement of heat-generating circuits and how airflow will cool them all. There is a reason why cold air enters from the front and bottom of the case, flows around all components absorbing heat and finally is exhausted through the power supply at the top and rear. It is a bad idea to run the computer with the case open; the internal airflow is gone, and even if you think that components will be cooled better in the open case – they’re not: hot air right above the circuits is no longer moved by fans, so components overheat.

Processors are by far the biggest heat generators in a computer. They need adequate cooling to take heat from the processor and transfer it to air. This is done by heatsinks. There are two elements of interest here: the material of which the heatsink is built, and the contact surface between the metal and air. First of all, full-copper heatsinks are heavier and more expensive than aluminium ones, but they provide a better transfer of heat from the processor to the base metal plate and from metallic fins to air. Note that because of the weight, some coolers for AMD processors will need to be attached to the motherboard with screws rather than clamping them to the plastic CPU socket, so make sure your motherboard model has the mounting holes and the space around the socket for that specific heatsink; all modern Intel motherboards have a standard system to attach the heatsinks to the motherboard. Secondly, the largest the compound surface of all metallic fins, the better will heat be transferred to air, so look for heatsinks with many, thin, large surface fins. Manufacturers will try to trick you with all kinds of stuff: aluminium heatsink with copper insertion where it touches the processor, or cyllindrical shaped heatsinks, or other weird stuff; I’m not saying these solutions are not working, but I’d rather use a large copper heatsink, such as the ThermalRight SP-97 for AMD AthlonXP processors.

Air needs to be ventilated through the heatsink continuously by a fan. The more air passes through the heatsink, the more heat it will absorb from the metallic fins. The key here is the volume of air. Since fans come in several sizes, usual dimensions being 40, 50, 60, 80, 92 and 120 milimeters, you can get the same volume of air pushed through with a small fan at high speed or with a large fan at low speed. The heatsink will accomodate only one or a few sizes of fans, though, and that might be a little restrictive sometimes. Many CPU cooling kits include a heatsink and a fan, but you might consider replacing the fan with a better one of same size, or just buy them separately for more flexibility. The problem here is that fans make a horrible noise at high speeds; you might not hear them at 2000 rpm (revolutions per minute), but at 4500 they’ll scare your neighbour’s cat. To move the same volume of air through the heatsink while keeping noise to a minimum, the best solution is to attach the largest fan you can mount on the heatsink; pick one which runs at lower speeds or get a variable fan speed controller. Some CPU coolers have temperature sensors; they’re not that great, and they will only run at minimum specified speed when the computer starts up cold – afterwards, temperatures jump up quickly inside the case. Ball bearing fans are quieter and more reliable than sleeve bearing ones, but they still need to be cleaned as often as needed to prevent vibrations and noise.

Some cooling specialists consider that it’s not too efficient to have the CPU cooler recirculate the warm air inside the case through the heatsink, and they suggest using a case with a special opening in the side panel so the CPU cooling fan draws cool air directly from outside. Others claim that the difference is insignifiant. If you are into case modding or extreme cooling, perhaps you should give this idea some thought.

Airflow inside the case is usually assured by the fan inside the power supply. Recently, power supplies with huge 120 milimeter fans appeared on the market – these will provide a very good airflow at slow speed (1200-1800 rpm) thus being very quiet. Other power supplies have two or even three regular 80 milimeter fans; doubling the number of fans doesn’t necessarily improve airflow, but adds noise. Finally, a few power supply models have temperature-controlled fans which run at different speeds based on air temperature – this is probably a good choice for most people.

If you don’t have a power supply with an oversized fan, it is a good idea to supplement airflow by mounting an exhaust fan at the back of the case, if it can be done. Again, keep in mind that larger fans at lower speeds are quieter while having the same results as smaller but faster (thus noisier) fans. Mounting a supplemental 120 or 92 milimeter fan at the back of the case is excellent.

If your case doesn’t have many air vents on the sides, it is usually a good idea to match or slightly exceed the exhaust fans’ total volume of air displaced with an intake fan mounted at the front of the case. This will prevent air and dust from being sucked in through every possible hole, even through the floppy drive slot and around the CD tray opening. If possible, pick a case which allows mounting a 120 milimeter fan at the front and also protect it with a replaceable, washable air filter.

A few people decide on replacing air cooling with liquid cooling. Basically, heat from the processor and graphic card is absorbed by liquid instead of air, then the liquid is cooled through a radiator mounted at the back of the case. This solution can be a lot more expensive than air cooling, not signifiantly quieter, and still needs the other components in the computer to have a minimum airflow.

The second source of heat in the system is the video card’s graphic processor. Often overlooked, this small fan can be the source of a loud, high-pitched noise. Luckily, there are solutions for replacing the heatsink and fan with better ones, both in terms of cooling as well as less noise producing.

The third source of heat is your hard drive. It heats up from spinning at high speeds, and the last thing you want to do is risk losing your data by cramming a bunch of hard drives together or placing the hard drive in the empty bay next to the floppy drive. Instead of adding one of those inefficient hard drive coolers (another fan in the case, another source of noise), look for a case with a rail of 3.5″ bays at the bottom, able to accomodate 5 to 8 hard drives. Mount your hard drive somewhere in the middle, where it will be cooled by the air coming in the case through the front vents (and possibly front intake fan) and it should run happily for years. Tests also indicate that a good contact between the hard drive case and the metal of the computer case helps it cool down and also prevents electrostatic charge from accumulating and zapping your data, so you might consider a good old-fashioned screw mount than plastic rails or rubber spacers between the hard drive and the case. Some people came up with a solution of suspending the hard drive with elastic cords to prevent vibration from being transmitted to the case; they overlooked the electrostatic charge problem because the hard drive was no longer grounded, and data corruption occured more often than usual.

You don’t have to be a noise elliminating freak (like me) to notice that your computer makes all kinds of noises. Some can be tolerated, while others are just too annoying or loud, especially when you try to get some sleep in the same room with your running PC. The components inside your computer are not all electronic and fixed. Some have moving parts, such as your hard drive, CD drives, and cooling fans. Each electric motor is a source of noise and it is a pretty difficult task to muffle the noise somehow without restricting airflow which cools down all the circuitry. Motors also generate vibrations, and these are transmitted to other components and the case; the entire metallic box can act as an acoustic chamber and amplify certain frequencies.

It’s usually easier to prevent noise from appearing than trying to mask it. For example, if you need to buy a hard drive or CD drive which you know is a source of noise, pick a model that is very quiet. For years, Western Digital hard drives were very loud both in idle time as well as when the heads were seeking, reading or writing data, while Seagate drives and more recently Samsung drives made efforts in keeping noises to a minimum through various technologies. Look on the technical specification sheet and look for the noise level; most people cannot hear noises with 25 or fewer decibels (dB) in intensity. 30-35 is more like a whisper, but it can be a difference between a low-frequency and a high-pitched tone, even if it’s almost quiet.

Cooling fans are also a source of noise. As the blades of the propeller “cut” through the air, the friction produces noise. The higher the speed of the fan, the louder the noise will be. Some fan manufacturers research new shapes for blades to minimize noise, but these products come at an extra cost. The rotor and the fan body connect in two points, where manufacturers can use either a ball bearing or a sleeve bearing. Ball bearings are more reliable in time because they are sealed and cannot be affected by dust; they are usually a little quieter than sleeve bearings, too. Look for fans with one or two ball bearings. Your power supply also has at least one fan – look for good quality fans when you purchase the power supply, because you will probably not want to break the warranty seal to clean or replace them.

Dust particles in the air can also attach to the blades unevenly and make the fan vibrate louder and louder. You should visually inspect all fans in your computer every few weeks or months, depending on how clean is the air where you live, and clean the underside of the blades with a damp cloth wrapped around a finger.

Last but not least, your computer case is important. If it is a cheap one, built with thin metal sheets and weak mechanical contacts between parts, it will amplify vibrations transmitted by hard drive and fans into a disturbing low-frequency noise. Pick a sturdy, heavy case made by a reputable manufacturer; attention to details, such as plastic mounting frames for fans, air filters and screwless installation usually indicate a high quality product. Friction also appears when air passes through venting holes of the case; if the holes are small or covered with dense grids, this only means there will be more noise (a soft woosh or hiss) generated there; look for cases which have wide open holes where the fans are mounted.

I have tried all sorts of noise dampening methods, from rubber stand-offs for the case, rubber grommets for screwing hard drive to the case, soundproofing the inside of the case with foam pads – but had little luck with them. Prevention by careful selection of components is a lot more effective. You might want to look for other sites and product reviews concerning silencing a computer, but everything you should know is right here.