Ok so in game after 1-2hours I crash after experiencing artifacts. I have fan on high 65-100% in game I am at 58-65 c. I know its not heating. I know it's not an OS issue and I have no PSU issues (650 watt antec PSU). This is for XFX 8800 GT XT (640-950) factory overclock. When I turn memory to stock it last's much longer before crash then when in stock over-clock, still crashes though just gives me extra hour before it does. I am thinking of sending it back but would like to know what the problem is or if others have had the same issues.  
 
It has crashed in various games, never at idle or just using windows. Recently I have rebooted and it skips over windows boot and then goes to BIOS and says BSOD a piece of hardware has prevented you form booting, then I reboot and windows boots. it has progressively became worse over time and now I am fed up, I rip COH and have lost many games cause of crashes lol.... please help!
 
e6850
4 gb crucial balistix 6400 ram
evga 680i LT
ANTEC TruePower Trio 650W Power Supply
http://www.memoryexpress.com/Produ [...] 4(ME).aspx
 
 
PS: These are his specs do not look at my specs this is a post for a friend who has forum accounts in other places but not here. He has had no answers, I thought people at toms can help him out. He has link to this forum he would appreciate some good help. I know his comp and issues so I reply ti your questions and answers, thanks.

I have the same issue with my EVGA 8800 GT KO (675/975 factory OC).  These cards are basically pushed to the limit and the stock cooler just isn't up to the task.  Although, I agree it isn't fully a heat issue as I've used an aftermarket cooler and ran the card at 35'C Idle / 42'C full load in all sorts of configurations and it still crashes fairly quickly.  Doesn't matter what driver version.  Problem as progressively gotten worse as well, so I'm RMAing mine.  This is a semi-common problem from a look at the forums.
 
The problem is definitely faulty memory on the video card.  The artifacts you get before/after the lockup pause before progressing towards a BSOD is a the textures getting all mixed up on the memory.  On my card, at this point, if I kill the game, I won't BSOD.  Because of where my faulty chip is, I'm actually able to play low memory games for hours without a problem, but demanding games the crash happens rather quickly.
 
You should definitely RMA it for replacement.  You paid extra for a factory (guaranteed) overclock, due to whatever reasons and it doesn't even run at Default 8800 GT specs...  No reason to ponder fiddling around with it more than you have since you have already done some troubleshooting on your own.  The faulty memory + poor cooling are only going to make the problem worse over time as you've experienced already until the card is rendered unusable.  

first off, sounds like a faulty card. RMA it. second off, perhaps there is a problem with the memory heatsink contact. RMA it. third, there could be a general cooling problem in your computer which affects the ram temps. try better case cooling perhaps. the 8800GT hsf pulls air from within the case and spits it out inside too.

While it may be possible for the others comments to be true, don't be so hasty to RMA it.. I recently upgraded to an evga 8800gt myself and had the exact same issue with random freezing during graphic intensive games like UT3 and Cod4.  I tried every possible trick to fix it, but to no avail.  Ultimately, I suppose it turned out to be a driver issue, as I resorted to a clean OS reinstall.  Honestly, I can't see how it was a bad driver, or how that would affect it crashing, I used drivercleaner and etc.  Then again, I didn't want to lose all my files, but I figured, heck, why not give it a try since nothing else was working.  In the end, it worked out for me and the cards running like a champ, and stable well past the 30 minute crashing point.  If in fact you do RMA it, and this turns out to be your issue, your simply going to find yourself in the same situation.  Hope this helps.

if i was in ur place. ill do what zeruin said. BUT again, the last solution is RMA it. which im not against.

  I hope it has nothing to do with his mobo, I've been looking at getting something similar for myself in the not too far distance future.

First off make sure he does not overclock this card as it is already overclocked.........second......I would get the bios for the card and reflash it...third...do the same to the mobo....and I have had issues with nvidia drivers myself so try the XG drivers.....they work much better for me......also check the fan that was installed...reseat it if you have too....use paste

Thank you all, really great advice. He is sending card back today. He has flashed the mobo bios more then once, reinstalled vista twice and has a very efficient cooling system as far as his case goes, he put a lot of time in making that right. (extra fan and proper directional airflow on antec p182.)He has also tried about every driver out for this card beta ones included and problem the same. He also really hopes it's not mobo problem and is getting same card as one he already has and is sending back to be replaced today. He was planning to run sli anyway in the spring but has had to get new card now cause he use's computer for more then just gaming. So thats what credit cards are for. I will keep you posted, the card that he is getting today will be tested today so he will know for sure if the card was faulty, thanks for helping him finalize his decision, more info here then he got fom other places.

um, I cant find a 780i LT anywhere. Did you mean something else?

this is where we got the computer parts for his build and this is his Motherboard. Sorry I made a mistake. 7, stupid me. it's 680i lt.
 
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