Recommend me a PSU

[fzdog2]

I recently picked up an Antec Earthwatts 500w PSU and am wondering if it will be enough for my new setup.

http://www.newegg.com/Product/Produc...82E16817371007

New Machine:
Xeon x3440 (i7 860)
evga p55 sli
2x radeon 5770
4gb ddr3
4 case fans
2 10k hdds
1 dvdrw

My calculations brings maximum system draw to ~400W, but I'm not to sure how much that would change with overclocking cpu/gpus.

 

[-Slacker-]

Well, I remember doing a similar calculation on the manufacturer's site and they recommended me ~450w for 2 5770s but with a less hungry cpu, 1 HDD and 2 case fans, so I'm guessing your system will need at least 500w ... I'd get a 550w PSU just to be sure.

edit: I ran the numbers in my head an I came up same as you, 400w ... that Antec's efficiency is well over 80% so I guess 500w would be fine, but you also need to take into account that PSU's loose a bit of their capacity with age, so I think you should only get the 500w model if you're not planing to keep it for too long...

 

[fzdog2]

Well here's the thing, I won't be finishing buying everything for at least another month. I found the power supply at Staples mispriced on clearance nationwide for 99.99-clearance = $36.50!!!! So i snagged 3 of them.

More or less, I just need to know if I'm at risk for overloading the psu especially if I get into OC'ing(air only).

 

[-Slacker-]

Not saying that the EA-500 isn't a quality product - it's actually (beyond) best-buy at that price, it's just that, although that PSU behaves very good at it's advertised capacity, if you say you're going to overclock the cpu as well then it might just not be enough ...

 

[VirtualLarry]

Those EA500s at Staples were certainly a good deal, but I would aim higher for your rig. I would go with an EA650, they are $75 at newegg right now. I don't think 500W is enough for a high-end quad CPU, and two graphics cards. Maybe at stock speeds, but not when overclocking is taken into account.

 

[Stefan Payne]

I don't think 500W is enough for a high-end quad CPU, and two graphics cards. Maybe at stock speeds, but not when overclocking is taken into account.

You think wrong, especially with 2 HD5770.

 

[VirtualLarry]

You think wrong, especially with 2 HD5770.

Well, overclocked i7-860 = 200W
motherboard 25W
DVD burner 18W
RAM 20W
HD 14W

Do the 5770s take LESS than 100W, under load, overclocked? Overclocked power consumption can double normal power consumption.

http://www.tomshardware.com/forum/273105-33-radeon-5770-power-requirement

Look at how Furmark causes 5xxx-series video cards to take 150% of their normal gaming power.

OP might be ok with overclocked CPU, and non-overclocked graphics cards, but wouldn't be able to handle furmark.

 

[TemjinGold]

Well, overclocked i7-860 = 200W
motherboard 25W
DVD burner 18W
RAM 20W
HD 14W

Do the 5770s take LESS than 100W, under load, overclocked? Overclocked power consumption can double normal power consumption.

http://www.tomshardware.com/forum/273105-33-radeon-5770-power-requirement

Look at how Furmark causes 5xxx-series video cards to take 150% of their normal gaming power.

OP might be ok with overclocked CPU, and non-overclocked graphics cards, but wouldn't be able to handle furmark.

Where are you getting these numbers from? 200w for an i7-860? And why would the 5770s need to be less than 100 watts? You do realize a 500w PSU actually gives you 500w, right?

 

[heat901]

I dont know I think the 500 would be cutting it close....

 

[-Slacker-]

You do realize a 500w PSU actually gives you 500w, right?

Isn't some of that going to be dispensed and wasted as heat (typically 10~25%)?

 

[fffblackmage]

Isn't some of that going to be dispensed and wasted as heat (typically 10~25&#37😉?

Kinda depends on how the manufacturer defines that number (peak or continuous), but generally, it's supposed to be the maximum continuous power output. Meaning the components in your system can draw only 500W from the PSU, while the PSU might consume more than that from the wall due to less than perfect efficiency.

Example: A PSU under 100% load draws 625W from the wall, but 80% efficiency means total output is 500W.

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Anyways, 500W is most likely sufficient under stock clockspeeds. Might be somewhat close, but probably still within PSU's limits. I'd feel safer with a beefier PSU for OCing though.