Is my PSU powerful enough?

[guren]

I got a Corsair TX650M
I would like some advice on what is an ideal watts to stop at?
I heard people say you can max it out, like the machine in Dells, but is that good for the PSU?
The watts figures below are base on uk.pcpartpicker (i'm not sure how reliable these figures are they sound about right to me)

My build
CPU 4670K {84w}
Stock Cooler (upgrading to H80i when next price drops {15w})
Asus Z87 pro mobo {70w}
256 SSD {5w}
500Gb 2.5" {15w}
500Gb 3.5" {20w}
1TB 3.5" {15w}
4x4GB Ram {18w}
6x fans {30w}
That makes total 272 watts

I want to either buy GTX760 (170watts) or GTX660 ti (150watts) will upgrade to SLI maybe next year or two.
I want the GTX 760
272+170=442watts
272+170+170=612watts (612/650=0.94%) will this be killing it?

also I don't think I have enough 6pin adapter right?

thanks in advanved

[MrJim]

If you're planning to go SLI in the future, I'd probably aim for a 750W or 800W unit myself, to err on the safe side. You need to allow for the efficiency of the PSU, and the fact that you don't want it to run the fan at full speed under load, ideally...

[ndaar]

Id agree with jim for single GPU its more than fine however 2 760s would be pushing it especially if you overclock at all. Id say get a 700-750 if you want to SLI.

[guren]

thx everyone
I''ll be looking for GTX760 now and buy it when the next price drops!
will upgrade PSU if I do decide to SLi

[kalniel]

Enough PCIe connectors is one thing, but those wattage estimates are out. A good 650W supply will be more than enough for SLI 760s with your other components.

[Pob255]

Yes, start with 70w for a motherboard is flat out ridiculous

Next you need to look at ampage not just wattage, also those gpu numbers are a little high
http://www.techpowerup.com/reviews/N...TX_760/25.html

[Willzzz]

Yeah 650W would be fine for SLI 760s.
Of course if there is a slightly higher watage model that takes your fancy it wouldn't hurt, depends on what is available at what price.
But you don't need anything over 650w.

So erm yes your current model provides enough wattage.
Ideally look at getting a 2x8gb ram set, that will put less stress on your memory controller which can benefit stability when overclocked.

[Scainer]

All at stock then it would be fine, but if the CPU, RAM and GFX cards all get overclocks, then I would expect possible issues in the future
(i.e. expect a 10 - 20% efficiency drop in a year or two)

Under normal load it would be fine but if / when stressed is the scenario i'm talking about.

[Willzzz]

??
In a year or two?
In that case it would still be under warranty and you just return it.

But really a good quality PSU will not degrade anywhere near that quickly.

[Willzzz]

http://www.vor tez.net/articles_page..._review,9.html

480w full load power draw and that's with an i7-3960X @ 4.5ghz

So that's 74% load on a 650w PSU under full power, a typical gaming load will be far closer to 50%.

HEXUS WHY YOU BLOCK ****** LINKS???????

[Agent]

All at stock then it would be fine, but if the CPU, RAM and GFX cards all get overclocks, then I would expect possible issues in the future
(i.e. expect a 10 - 20% efficiency drop in a year or two)

Under normal load it would be fine but if / when stressed is the scenario i'm talking about.

You won't get anywhere near that level of level of degradation on a PSU. Period. If you do, it's faulty.
Under stress or not doesn't really matter that much - look at PSU efficiency curves. It's the MTBF you need to consider more than anything else.

As kalniel said - that PSU is more than enough for the job.

PSU Manufacturers (and by that, I actually mean the companies that re-brand CWT, FSP and so on...) have done an amazing job at convincing people you need an obscenely large PSU and need to replace it every few years.

A good quality PSU will last for years. The system I'm typing this on has a PSU that's got to be close to 9 years old now and there is simply no reason to change it. A bit of me dies inside when I hear people saying a PSU degrades by about 10% a year under normal use. It's not like there are journals and papers out there with the maths to work these things out....

edit - the other thing that people don't seem to understand is that capacitor ageing doesn't have that much of an impact on the PSUs total power output. This is another myth that has been started because of that god dam extreme power calculator which throws out an unbelievable amount of bad information.

Time and time again, I see people doing something like this:
600W - (2 years * 10% degradation) = 480W, and that you shouldn't expect any more than this from the unit.

This makes me irrationally angry, because it has zero basis from any research done on capacitor ageing.

What capacitor ageing does cause is higher ripple, sudden loss of power, unstable voltages and so on...none of which you want either.

The single, most important thing for keeping a capacitor healthy is temperature. Given that the inside of your PC isn't really that hostile, it's not a concern for the vast majority of people. More so given the huge fans fitted in a PSU these days.

[Scainer]

Is it not prudent to plan for prevention of any issues? I was looking at worst case scenario, e.g. the PSU high usage 24/7, but to be fair I didn't really calculate the quality into the equation. Anyhow....continuing with worst case scenario assuming this is correct

80PLUS bronze is 81%ish on 230v efficient so 650w = 526.50w
Using the OP figures of 612w max then the prudent choice is a 750w PSU

[Willzzz]

Erm..

He doesn't have a 526.5w PSU.
Power draw at the wall is irrelevant.

The 612w figure is not accurate.

[kalniel]

Is it not prudent to plan for prevention of any issues? I was looking at worst case scenario, e.g. the PSU high usage 24/7, but to be fair I didn't really calculate the quality into the equation. Anyhow....continuing with worst case scenario assuming this is correct

80PLUS bronze is 81%ish on 230v efficient so 650w = 526.50w

Wrong way around. An 85% efficient 650W power supply will provide 650W. A 90% efficient 650W power supply will provide 650W. A 70% efficient 650W power supply will provide 650W. Spotting the pattern yet? Now, they will cost different amounts of electricity at the wall for any given load, but they should all be capable of supplying exactly the same load.

Using the OP figures of 612w max then the prudent choice is a 750w PSU

1) That's wrong, see above. 2) The OP's figures are also wrong.

You can't really meaningfully apply prudence until you get some semblance of correctness, and doing that, a 650W is more than prudent enough for SLI 760s.

[Willzzz]

If anyone wants to send me two 760s I'll more than happily run them on my 600w PSU, any offers?

[Scainer]

Nice to know its the other way. i.e. the 650w PSU draws about 800w
Next question... Why are cheap power supplies always said to have untrue figures? E.g. a cheap 800w PSU.
Is it just a misunderstanding and really its about the amps that might be low?

By the way I read a review on SLI 670's that mentioned a minimum recommendation of 700w, hence my view point. I am trying to find it now through my history.

Just to contradict myself looking for the review I found this one...

GeForce GTX 670 SLI provides near-linear performance upscaling over single GTX 670. With a power draw of just 28W in idle, and 250W average load, the GTX 670 SLI, for the first time, makes a dual-GPU flagship card look silly, in terms of performance/Watt. Even an efficient 600W PSU should handle the GTX 670 SLI just fine.

Found it but to be honest there is no reasoning behind it as in the tests it drew 433w in full stress

Here is Guru3D's power supply recommendation:

GeForce GTX 670 - On your average system the card requires you to have a 500~550 Watt power supply unit.
GeForce GTX 670 2x SLI - On your average system the cards require you to have a 700 Watt power supply unit as minimum.
GeForce GTX 670 3x SLI - On your average system the cards require you to have a 850 Watt power supply unit as minimum.

670 SLI had 489w with a Intel Core i7 3960X