random BSOD, display reverts to 800x600

had a system in which was experiencing random BSODs, mainly during gaming, as well as sometimes the display reverting to very low resolution modes.

i checked the system logs and the wide variety of STOP codes suggested none of them were individually worth pursuing, and that there was likely a hardware (memory) problem.

i ran some memory tests for a few hours and they came up clean, but then some internet research found an interesting quote from the MSI website (it was an MSI motherboard) that said that the default memory timings might be too aggressive and could result in an unstable system. they actually expect you to manually underclock the RAM just to get a working system!

i found this a little odd, so went to investigate the DRAM settings in the BIOS, and that's when i noticed the default clock speed for the RAM was 200mhz, the correct setting for DDR400 RAM, but the machine was only fitted with DDR333. the correct clock speed for this is 167mhz. so i adjusted the setting, and the BSODs were gone.

there still remained a problem with the displays reverting to extremely low resolutions. this was caused by a lack of power - there was only a 450w PSU powering a dual-core 64-bit processor, 2gb of RAM, several optical and hard drives, and 2 nvidia graphics cards in SLI configuration.

the problem with the displays going bad was interesting, but then i noticed that there was only a 450w power supply, powering a 64-bit dual core system with 2gb ram, several drives, and 2 nvidia graphics cards in SLI configuration. upgrading this to a 750w corsair PSU solved that problem.

WinXP : stop 0x0000000a during safe mode startup

Got an old XP home box in today that wouldn't boot. Regular windows boot just hangs halfway through loading, and safe mode produces a BSOD with STOP code 0x0000000a.

this code normally points to bad drivers or to faulty RAM. with it happening during safe mode, we can happily rule out most cases of bad drivers. so i ran memtest86 for a couple of hours and it didn't produce any errors. normally I'd run memtest for at least 12 hours before accepting a "pass" result, but given that the symptoms are showing so quickly (during bootup) i figured a couple of hours should be enough.

to be sure, i then swapped the RAM out for some sticks i've got lying around, and it still would not boot, and still produced the same BSOD.

the next task was to start eliminating pieces of hardware, and during this process i discovered that pulling the power to the two CD drives enabled the system to boot. however there was clearly not a hardware fault with the drives themselves, as having either one of them powered up prevented the system from booting.

so, with the 2 drives disabled, i booted the system, and saw that the most recent software that was installed was an old version of roxio easy cd creator. so i uninstalled this, and ran the registry patch available from http://www.aumha.org which forces windows to re-install the cd drives upon next reboot. sure enough, with the drives re-connected, windows booted successfully.

conclusion : the roxio software had installed a driver for the CD drives (most likely for UDF support) which was faulty or incompatible with the system. as windows will always load the drivers for CD drives even in safe mode, there was no way to uninstall the driver or roll back the system without first disconnecting the drives.