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Estimating PSU requirement for new graphics card, just barely enough

Last response: in Components
December 29, 2011 7:57:53 AM

I want to get a Radeon HD 6850 but I'm not sure if my PSU can handle it.

Current set-up:
AMD Athlon II X4 645
Gigabyte GA-880GMA-UD2H
4x2 sticks of DDR3 RAM
Antec Earthwatts 430W
A wireless card
A couple hard drives and a bunch of USB peripherals.

I plugged it all in to this calculator

...and it came out to 423W with 20% capacitor aging. So, what happens if I plug in a few extra hard-drives and my computer tries to draw just a little over what my PSU can put out? Does the computer just shut down or can I fry something I'd rather not?

Will I be safe or am I resigned to buying a bigger PSU sometime soon?
a b ) Power supply
a c 92 U Graphics card
December 29, 2011 8:04:29 AM

that psu is good so a 6850 will have no problem. It will be able to pull more than 430w for short ammout of time if needed, you computer will not be pulling more than 300w most of the time.

as you can see the whole system draws less than 300w of power when fully loaded, that is with a more power hungry CPU.

if you do go over the limit your psu can handle you'd shutdown, always a possibility of damaging something but its no more than if you shut off the psu before shutting down the pc.
a b ) Power supply
a b U Graphics card
December 29, 2011 8:26:51 AM

The calculators over-inflate EVERYTHING so you go off and buy a bigger PSU than you need.

Esrever is right, you will be fine - Dont ever cut it too fine though, gather some knowledge before buying a Graphics card, but use benchmarks and recommendations from us lot rather than Calculators and Vendor requirements.
I personally will never go below 850W, I like to be prepared for any event (Like a promotion which = another PC component xD )
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a b ) Power supply
a b U Graphics card
December 29, 2011 12:36:45 PM

I always go over a little what I think I need just to be safe, just get yourself a quality 500w supply with bronze or better efficiency rating.

Best solution

a c 248 ) Power supply
a c 179 U Graphics card
December 29, 2011 10:11:25 PM

20% capacitor aging grossly inflates things, your PSU might lose 20% of its capacity after about 10 years, its a good unit and isn't going to age that poorly for quite a while, you are fine with that PSU in that system for quite a while.
December 29, 2011 10:52:38 PM

I favor bigger than estimated PSUs to have room for expansion down the road

Even though I can use 650W PSU I would still pay $25 more for 850W
December 29, 2011 11:56:04 PM

Best answer selected by Moniker_69.
December 29, 2011 11:56:21 PM

Alright guys. I just made the order. Thanks for all your help!