Constant bluescreens / reboots.

I have a small problem.

Just recently, my machine has started to exhibit very erratic behaviour - whenever I'm playing a game for longer than about 2 hours it will inevitably either lock up (keeping the game audio stuck in an endless loop in the background), instantly reboot or throw a random BSOD at me - I've counted three different stop errors it's given me thus far - the first one mentioned a "Bad Pool Header", the second informed me that "The driver for the display device got stuck in an infinite loop" and the third that "A wait operation, attach process or yield was attempted from a DPC routine".

It seems to prefer certain games over others - I've played the BioShock Demo maxed out repeatedly for four hours or so with no problem, spent almost all day playing Oblivion with only a single hiccup, but when it meets something like Colin McRae: DiRT I'll be lucky to get an hour's play out of it before it promptly dies. Note that this *never* happens unless I'm gaming, in every other usage scenario the system is solid.

The specifications can be viewed in my profile.

My initial thought was that it was overheating, but upon checking the system temperatures everything looks normal - under load the CPU is around 45 degrees and both 8800s are in the mid 60s to 70s, which from what I've garnered from a little research is about right. Secondly I thought there might be an issue with the power supply, however I think this is extremely unlikely as it has literally just had a brand new 650w unit installed. (FYI the symptoms were present before the installation of the new PSU). I then tried playing musical chairs with ForceWare versions (making sure to clean between changes using DriverCleaner), thinking it was perhaps a driver related problem, but to no avail.

My last idea was that I might have dead or dying RAM, so I'm going to fire up MemTest in a second and leave it to run overnight to find out for certain. At the moment I'm in the process of throwing every diagnostic tool known to man at it (including an AV scan to be on the safe side) in an effort to get to the root of the problem, as it's doing my nut in.

Does anyone have any ideas?

Cheers.

Sounds like a software issue......downloaded any new drivers for say a new gfx card recently?, or any other programmes thst may cause a conflict5.n Sound card drivers have been the bain of my life to date, and if you have recently installed a new sound card,m then this is worth investigating.

I recently installed a second 8800GTS, however that didn't require a change in drivers...

Anyway, after an 8 hour run of MemTest it returned 2 errors. Guess I've found the problem...

What settings are you running the memory at?

It could be overheating, if you've got a spare 80mm or smaller fan knocking about you could try connecting it to the memory. Use a couple of bits of wire feed it through the fan and around the clips on the memory sockets to hold it in place
EG
http://i200.photobucket.com/albums/a...2/DSCF1894.jpg
Thank's to Daza for introduceing me to this idea, I've currently got a 55mm fan off a P3 Slot1 cooler wired to my memory :D

The memory is running at stock speeds, and there's plenty of room for air to circulate around the DIMMs - most of the cabling is routed round the back of the case, so nothing's obstructed by a rat's nest of cables. :p

The only change I've made is to alter the command rate from 1T to 2T. Running the RAM at 1T renders the system nigh on unusable - at first I thought this was just an idiosyncrasy of the chipset, but from the look of it now it might well have been the RAM itself at fault.