Using GPU-Z and Everest both, the fan speed is hanging around 50 C when the IGT games goes blank.
I went and looked at a multitude of event logs, I believe at your suggestion. For that particular game, it says the game caused a audio timeout of 30000 milliseconds. I don't know what's with that. Since I don't have a sound card, I'll install the latest MOBO drivers again. However, I didn't have this problems until the video cards started acting up and don't know why it would cause me to lose video.
After that, I decided to run the Microsoft Fix-it center hardware check. Lo and behold, the problem card I had reinstalled the other day and, which, Vista installed the driver for, was turned off by Vista because of Code 43 without giving me a message. So I know that card is kaput. It's no wonder Riva wouldn't let me tweak it (it couldn't find it).
So the lone card is doing a good job. I'm working with the vendor to try to get the other replaced. The vendor says it's EVGA problem and EVGA says it's the vendors so I'm in a catch 22. If I can't get it replaced, I may just go with one card or consider buying a new one to replace both old ones. I'm thinking of the GTX 295, if I can find one, and assume it will run on my 780i MOBO with 600 watt power supply. Off to hunt down the audio timeout problem fix. Thanks for your helpful suggestions.
 

Hey good to hear,  but chances are it will fault out again.  If it is sometimes recognized and sometimes not, it sounds like the card is on its way out.  If you registered the cards with Evga within' 30-days they should have no problem RMA'ing it. 
 
Also a Gtx295 on a 600w is a little iffy, depending on what psu you have.  A better, more efficient option that would run fine on a 600w psu and have DX11 support would be a GTX460 1gb, or a HD5850.
 
 
GL

I would think Evga would be responsible for the warranty if you have the invoice for the pre-built comp.
 
If you can validate that your warranty is NON existent, and you want to take a chance,  there is a baking method that has rived many 8800gtx/gts's.  Yes baking in the oven.  With the cards running hot all the time, some of the solder will actually soften,  baking in the oven will reflow the solder to the joints.
http://forums.guru3d.com/showthread.php?t=313769
http://hardforum.com/showthread.php?t=1421792
http://www.youtube.com/watch?v=_taI-CkPD3M
 
And yes a single gtx460 1gb will be faster than 8800gt sli.
 
Keep in mind the new HD6850 and 6870 just came out and they both beat the gtx460 1gb.  And the hd6850 is currently $20 cheaper, but the 6870 is a little beast.  They are the mid range cards, so when the high end new ati cards come out these prices my all drop a little more.
 

I agree the gtx480 would be overkill for your needs and psu.
 
A gtx460 768mb is about equal to 8800gt sli, the gtx 460 1gb being ~10% faster than its brother,  I would put it as an upgrade.   Just to put all of the cards in context so you can compare.
 
I'm not sure about those benchmarks from there,  it is showing the gtx460 owning the charts pretty much, even beating the hd5850, which is very suspect.  Here is a very reputable site that has everything you need for pc gaming (reviews, benchmarks, news, every driver, applications, and ect)
http://www.guru3d.com/article/radeon-hd-6850-6870-review/
 
 

needs working links

Hello.
 
The update is only for evga reference 8800gt 512mb cards.  The updater will show up and upon bios verification will close if it sees a non-specified card.  Thats why it wasn't showing in the task manager, it opened and then closed and it didn't do anything, because it its not an evga card.
 
Also removing the drivers won't harm anything.  I would reinstall the drivers and use msi afterburner and make a custom fan profile.

rockeyaaa

Hey nick i would be very thankful to you if u give me the link of the original  bios of 8800gt alpha dog coz  i told you that my card is having artifacts on screen and i cant afford a new card

 
You are on the wrong forums.
 
You do realized that you applied another manufacturer's BIOS onto your card made by XFX, which is not recommended by any vendor and very likely voids warranty.
 
If you are looking for the original BIOS, you will need to contact XFX for that, which I doubt will provide, since you voided your warranty.
 
EVGA would not have a BIOS for a XFX product.