PSU Req's for new gfx card?

Just a quick question. I’m contemplating upgrading my video card. I’ve noticed that most newer nVidia (no ATI!) cards (nvidia GTX260, 280, etc) all require a ~525W PSU. Mine is only 485W (Enermax).
However, my system specs are different from those in the ‘recommended’ system they use to calculate those requirements.

Using the Extreme PSU calculator (eXtreme Power Supply Calculator), with my specs filled in and the desired card indicated, I’m told I need ~350W PSU, which suggests my current one would be fine.

Which should I believe? Or should I upgrade the PSU regardless, just to be safe?


Having in suffcient power is unlikely to break your graphic card. You just won’t have enough power to run it properly and it either will not work, or you will get strange artifacts and it will degrade after seconds or minutes and maybe eventually freeze.

The problem is the degraded effects are difficult to associate with being due to insufficient power .

But it should not break the graphic card. At least that was my experience where I put in a nVidia GeForce 8400GS PCI card (not PCI-3, but PCI) in an old PC whose power supply after some years had degraded below its specified value and could not drive the card (even though on paper spec it had the power, … ) . With the VESA driver, my card worked fine. With the proprietary driver, it gave artifacts and eventually would freeze. When I put the card in a PC with a newer power supply the card worked fine with all drivers. ie. older PC could not driver the card with the proprietary graphic driver, where the proprietary graphic driver required more power.

So if you detect the card does NOT function, maybe then you could rush down to the local shop and buy the power supply you need. Just make certain there IS a power supply in the local PC shop that WILL fit/work as a backup option in case the graphic card does not function properly.

Excellent, thanks for the help!

You could also put a power-consumption-meter between your pc and the net, to see how much power it actually uses; if it’s consumption is well below the spec of the PSU and it functions allright, you should be fine.

I actually had some artifacts/hangs after installing a new card. After upgrading the PSU, the problem persisted; turned out to be a driver problem… :\