Video card problems got my stumped.

So im gettin video display issues i have a 2900 XT and a certified 550 watt psu runnign cat 7.10. I'm having issues with UT3 (I reboot after a few minutes of gameplay) and Tabula Rasa (Graphical gliches) but games like world in conflict on max res run fine, temperatues idle are about 50C 60C-70C in game which is high but tis a 2900 so i kinda expect it. This is what the grahics error looks like in Tabula Rasa
http://img150.imageshack.us/img150/677/wtfug6.jpg

Any idea's whats going on should i force downgrade to cat 7.9? instead of roll back drivers?

 

what amps is listed for your 12v rail on side of power supply? Just because it's "certified" doesn't mean a thing. Almost all power supplies are "certified" You may still be under powering the card.

 

16Amps max on both 12v rails, .0.4 Amps minmium, I did downgrade to cat 7.9 I will try adjusting the settings but how coul that effect anything, (UT3 is set to max and Tabula Rasa set to max) Wouldnt is draw the same power anyways? on a side note, man my character looks really pale....

 

Just started up tabula rasa on Low settings no graphics problems weird ran it up to very high then fine tuned the settings apperantly when i enable dynamic shadows things start messing up, i havent tried UT3 yet

 

So now ther eis a new problem, after awhile of playing Tabula Rasa my computer will just reboot, i havent tried it with any other games yet tho... Any ideas?

 

So i submitted to Diamond Multimedia (maker of my vCard) and they said "Hello. The card requires at least a 750w power supply. That is the minimum requirement just to run the card for basic usage. If you are a gamer, you should go with something a little higher. This very well may be the factor in the card not performing at its highest potential."

so i guess i need more power?

also whe i open up every ultimate edition and look at the sensors it sayd GPU VRM with a electricity sigh next to it and "GPU VRM 25.74 A" im assuming that 25.74 Amps is that corrent? how much should it be pulling

 

it will pull more amps if the voltage drops when under load because it is still trying to render frames. This causes more heat also. If a 750w is recommended it probably pulls 30+ under load. Get a good quality power supply like antec as an example. The cheap "certified " ones will get you right back to where you are now.

 

That was jsut 25Amps idle in windows, my current PSU is an Antec True Control 2.0 550watt now i just gotta save some money to get a better PSU i guess Also when shopping for new PSU's what does it mean by efficency like say you get a 1000watt PSU and its efficency is 80% does that mean its only producing 800watts? or the amount of power being drawn from my wall outlet is 1200watts?

 

a pc uses only as much as the system needs. Efficiency (i believe but I may be wrong) is comparing how much it draws out of the wall versus how much it puts to your pc. In example it takes 1250 watts from the wall socket to make 1000 watts usable power in the pc.