• Competitor rules

    Please remember that any mention of competitors, hinting at competitors or offering to provide details of competitors will result in an account suspension. The full rules can be found under the 'Terms and Rules' link in the bottom right corner of your screen. Just don't mention competitors in any way, shape or form and you'll be OK.

Power requirements of a GTX 280

Associate
Joined
12 Aug 2005
Posts
1,025
Location
Team 10
After recently buying one of those cheap 280's, I suddenly had this nasty thought that my PSU isn't up to the job.

It's an old (2 years) 750W FSP PSU with 4 12v rails. I've read that the 280 wants a minimum of 40A and according to this review, that only leaves 10A for the rest of the system?

Are bad things going to happen or am I just being over cautious?
 
Can I also ask (sheerly for future upgradability purposes) what the minimum requirements for an SLI config with these cards is?
 
Can I also ask (sheerly for future upgradability purposes) what the minimum requirements for an SLI config with these cards is?

Power consumption ratings are all on this page of Bit-Tech's review. Its a good informative article in its own right.

Its interesting to note that the 295 in quad-sli only consumes 670w in an overclocked core i7 rig at load in Crysis. Not as high as I expected.

GTX280 SLI = 545w at load.
 
Last edited:
It's an old (2 years) 750W FSP PSU with 4 12v rails.

Hi NightmareXX, have you got a link to the manufacturers site of your power supply unit and/or do you know the maximum amount of amps that each of the +12Volt rails can supply?

I've read that the 280 wants a minimum of 40A and according to this review, that only leaves 10A for the rest of the system?

The 40 amp rating will be for the entire system not just for the graphics card itself. :)

Can I also ask (sheerly for future upgradability purposes) what the minimum requirements for an SLI config with these cards is?

Hi Natima, a single NVIDIA Geforce GTX 280 has the potential to draw around 240 watts which equates to 20 amps. Two of these graphics cards could potentially draw 40 amps. In reality though, they will likely to draw a bit less than that. However, to be on the safety side, you should always really take the maximum amount of power a card could possibly draw as if it was going to draw about that much when it's under load.

You then have to account for the other components in your system. If you have, for example a Intel Core 2 Quad Pro Q6600 overclocked to around 3.3GHz, on most chips an overclock of 3.3GHz shouldn't need a massive increase in voltage so it should draw no more than 150 watts which equates to 13 amps. Then add a couple of hard drives rated at one amp each and then some for the extra headroom, you are looking at around 57 amps.

In conclusion, you are really looking at a power supply that can supply at least 60 amps such as the Corsair TX 750W ATX2.2 SLI Compliant PSU. :)

The coolermaster's any good? Anybody know?

I can't say I have ever heard anything bad about any of the Coolermaster units. However, in terms of the amount of power then can supply compared to say an equivalent Corsair unit, they aren't actually quite as powerful.

For example, if you take the Coolermaster Real Power 520w unit which can supply a maximum of 34 amps on the +12Volt rail. If you then have a look at an equivalent rated Corsair unit, the HX 520W which can actually supply a maximum of 40 amps on the +12Volt rail so it’s slightly more powerful. :)
 
Last edited:
I'm pretty sure that each rail is rated to do 15A constant with 18A burst. I do know that my PSU is no longer listed on their site as it's so old.

Seeing as the 40A is for the entire system, I should be fine yea :)

I do know that the rails are split up into CPU, PCIE 1, PCIE 2 and SATA/Molex so that'll be 30A for the 280 alone which should be more than enough :)
 
Back
Top Bottom