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New graphics card - Computer shuts down in games.

UPDATE - Before i go ahead and order a new PSU i just want to say that my CPU is overclocked to 4.4 at the moment.... I'v had no problems with that at all and that speed along with my 2 x 5870's in crossfire ran fine...

I just took off the overclock and ran the bioshock benchmark again and it worked this time...

Does that definatly mean its the psu then and it it a case of the system needing less power because i took the overclock off so the card didnt crash it?

I just wanted to say my cpu has been at 4.4 for months and lots of 3dmark 13 runs in that time too and never had any issues with my pc shutting down.
 
Matson said:
I was also wondering with the cables... can you just leave the ends that are connected to the components in place and just remove the other ends from the PSU and connect them up to the new PSU? I would imagine they would be the exact same type of cables no?
Click to expand...

My advice would be to use the cables provided with the Corsair psu and remove everything associated with the old PSU from the case.

Keep us posted as to how you get on.
 
demon8991 said:
My advice would be to use the cables provided with the Corsair psu and remove everything associated with the old PSU from the case.

Keep us posted as to how you get on.
Click to expand...

Yeah i will i'v gone ahead and ordered the AX860 either way it should be much better and more efficient than the ancient arctic pro that im using now.
 
Its very likely not enough juice on the 12v rail. U checked the sticker on ur PSU? Assuming its cheap its probably got 4 readings on 4 rails.
 
Matson said:
I was also wondering with the cables... can you just leave the ends that are connected to the components in place and just remove the other ends from the PSU and connect them up to the new PSU? I would imagine they would be the exact same type of cables no?
Click to expand...

In my experience cables from different modular PSUs won't fit.

Andi.
 
Matson said:
Lol yeah that was just part of a ton of benchmarks i was doing lol.
I was thinking though. I had no issues when i was running 2 x 5870's in crossfire and the power requirements arn't much different to a 7990 are they?
Click to expand...
Not sure but perhaps its a multi-rail power supply and was serving each 5870 off a different rail but is trying to serve the 7990 off a single rail and can't handle it?
 
Up to 20A per rail, 4 rails, not exceeding 72 amps total. Sounds more likely it's overloading a rail in the PSU. I take it the 7990 has two 8-pin power connectors? Try moving them to different rails on the PSU maybe?

Edit: Or if they're both on one rail then move them to be on different ones of course!
 
Some PSUs have all the 12v power on a single rail (i.e. it monitors them collectively rather than singly), making it all available. That's the current popular solution, for reasons like the OP is experiencing. A few years ago it was viewed as better to have several rails, I can't really remember why. Maybe someone with more knowledge can answer properly!

Edit: The reason to have several rails each with it's own OCP is safety / protection of equipment. With a very high wattage supply you could end up with HUGE currents not tripping the OCP and so a short could cause lots of damage. Perhaps for a PSU of the OPs wattage a couple of rails would be better than 4 though :)
 
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I guess either way i should find out tomorrow as i ordered the ax860.
I mean i even took my overclock off and my i5 3570k is running at stock now but it still went off after the second valley run. Could it be an efficiency issue... and the PSU not providing anywhere near the 950watts that it says...Im guessing it most likely might be something to do with the 12v rail as like i mentioned iv been running 2 x 5870's in crossfire before this and im pretty sure they use as much watts if not more. Although i have experianced this in the past with my 5870's when i had my i7 920 cpu and my cards in crossfire it would shut off occasionally and reboot up when i had loads off effects on screen.
 
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I was going to suggest that before you buy a new PSU you should try either lowering the clock or bumping the voltage on the GPU. It is not uncommon for cards to come overclocked from the vendor with insufficient voltage ...
 
I wanted to show this... This is how the PCI-E connecters are hooked up... Theres one main wire.. But then as you can see in the left socket the wires going out and then straight into the right socket... Does that look okay? Shouldnt it be two completely different connecters? Does that mean its running off one rail for both connecters? I mean these are the two 8 pin connecters, then i have 2 more that are only 6 pin.

 
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This is what customer service basically said...

Hi Matson,

Modern PSU's have a single, extremely highly rated 12V rail, these are ideal for high draw graphics cards. However, supplies of your vintage tended to have multiple, lower rated rails which could not be combined to power a single device. The specs of your supply show this to be the case.

For example, a Corsair 600W Gamer Series PSU have a single 50 Amp 12V rail but your supply has four 20 Amp 12V rails.

On the face of things your PSU would win hands down but when you bear in mind that the power requirements for a 7990 are about 375W (which equates to about 32 Amps) you begin to see the problem.

In short, your suspicions are probably correct.
 
Thats both connections on one single spur from the PSU, try putting the 2nd connector onto a different spur - you have 4 rails in there, use two of the otherwise unused (i.e. dedicated) ones for the 2 x 8pin connections. If you only have two on a single spur (e.g. its not SLI/crossfire rated), most cards will include a molex to 8-pin adaptor so you could use that off another spur.
 
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What do you mean exactly....Do you mean switch something over on the actual PSU itself? Theres only 2 PCIE wires... That one which has both the 8 pin connecters attatched and another one with both 6 pin connecters and i can only use the 8 pin on this card.
 
Also theres no molex to 8 pin adaptor that came with the card..

heres another picture showing all the PCI-E connecters... The two 8 pin connecters are both on one single wire.. And then the two 6 connecters on 2 seperate wires..

 
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