24/02/2008 - Sunday

Wow, I hate computers sometimes

Last weekend I had some stupid weird problem with my computer. I rebooted it (as I do every Sunday morning), started up the programs I usually have running (winamp, utorrent, etc.), then fired up the defragger to clean up the C: drive (another thing I do every Sunday morning). This is where the problems started. Everything ground to a halt and the music went sporadic, like there was a ton of disk access. I left it for a couple of minutes to see if it would clear itself, seeing as I wasn't running anything that would cause all the disk access (I hadn't actually started the defragger at the time, so it wasn't that causing it). I got bored of waiting, so I decided to just restart it and try again. So I hit the reset button, watched the BIOS flash past, then it stayed at a black screen with the hard drive light on constant. So I tried it again. Same thing. Tried it a third time, and this time it flashed up that there was a disk read error. My mood suddenly dropped as there was some stuff that I hadn't backed up yet and I didn't really want to have lost it due to a dead drive.

Invisible hard drives

I have two drives in my computer (a 300 GB and an 80 GB) and I wasn't sure which was causing the problem, although I was guessing it was the 300 GB one as that's the drive that has Windows on the C: partition (it has four other partitions on it). I restarted the computer again and entered the BIOS to see if it's not seeing one of the drives. It surprised me as neither of the drives were visible (in hindsight I should have tried replacing the IDE cable, but I didn't think of that at the time). This was kind of confusing as I was expecting at least one to be there (if not both).

Getting my hands dirty

I decided to dive into the guts, unplug one of the drives, and see if the other one then becomes visible. I did the 300 GB drive out first as it was the easiest to get to. Turned the computer on and entered the BIOS and the disk was visible. Rebooted again and let the BIOS continue and it came up with the message about it being an invalid system disk, which was good. I plugged the 300 GB drive back in and unplugged the 80 GB drive, turned it back on, entered the BIOS, and, surprisingly, the 300 GB drive was also visible! Rebooted, let it continue, and Windows booted perfectly fine. Strange.

Kinky drives

I rebooted again and entered the BIOS yet again and took a look at where the drive was placed on the primary cable. Turns out it was the slave device. This got me a bit confused as the 80 GB drive was also the slave device when it was plugged in (different plugs on the cable too). The 300 GB has always been the master device as I hard set it with a jumper, and the 80 GB has been the slave (no jumper = slave for the drive). Why was it suddenly showing them both as the slave device? Maybe this was the problem? If both the drives are attempting to be the slave device then it was obviously confusing the BIOS and it thought that there were no drives at all.

Cable select

I decided to put both drives into cable select mode and let the BIOS and the cable work out which drive should be the master and which should be the slave. Changed the jumper on the 300 GB drive and put one on the 80 GB drive (luckily I have spare ones), plugged them both back in, turned it on, entered the BIOS, and only the 80 GB drive was showing as the slave device (no master device at all). I was getting annoyed by now (it had been about three hours since the problem started, due to going for a shower, stopping for lunch, etc.) so I switched the plugs over to see if that made any difference. Turned the computer on once more, entered the BIOS, looked at the drives, and both of them were visible with the 300 GB as the master and the 80 GB as the slave. Hurrah! Rebooted, let it continue, Windows booted and everything is visible on both drives. Hurrah again!

One week on

It has been a week now and the computer has been restarted a couple of times (had to fiddle with the network card settings to get a better network speed) and there was a very brief power cut at the beginning of the week (brief being less than a second, but long enough to interrupt the power), and everything is still working fine. I rebooted it again this morning before running the defrag and everything is still working fine. I have absoutely no idea what caused the drives to play up, nor why switching the plugs over managed to fix it. Maybe the cable is slightly faulty, but it's working for the time being. If it happens again then I'll swap the cable over with the secondary cable and see if that works (at least it's cheaper to buy an IDE cable than it is to get another drive).