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Would 550W PSU Suffice For ATI 5870 and i7 920?

I think 550W would work but i believe that system is going to draw ~400W of power. I would prefer more breathing room in case you would like to overclock either component. And the price isn't far off:

Antec EarthWatts 650W: http://www.newegg.com/Product/Produc...82E16817371015

OCZ 700W modular: http://www.newegg.com/Product/Produc...82E16817341018

similar cost but both would provide a little more juice for the overclocking/newer components.

*EDIT* PS I vote the OCZ modular PSU. Get rid of some extra cables and pretty solid price.
 
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MarkLuvsCS said:
I think 550W would work but i believe that system is going to draw ~400W of power. I would prefer more breathing room in case you would like to overclock either component.
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It will draw ~300W unless OCed. 550W is more than enough.

*EDIT* PS I vote the OCZ modular PSU. Get rid of some extra cables and pretty solid price.
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Earthwatts is definitely the better quality PSU.
 
The CORSAIR VX550 is an excellent choice for you. It provides much more power than enough to handle your system. If the price is good, go ahead.
If you are thinking about doing 5870CF, I would go for a higher wattage PSU (at least 600W and four PCIe connectors).
 
5870CF is not a model of a graphic card. It means CrossFireX. ATI CrossFireX technology enables two (or more discrete graphics cards) to work together to improve system performance.
Therefore, if you are thinking about installing a second graphic card, as I have said before, I recommend you to go for a 600W PSU (at least) with four PCIe connectors. If you have fun enough with only one 5870 graphic card, the Corsair 550VX is much more than enough for you. Don't worry.
 
PSUs work less efficiently in the upper 50% of the power range - waste more energy, produce more heat. High end system builders calculate total watts for 2x maximum load for that reason. If you think macimum load would be about 300-400W for your system then you should be getting 600W to 800W PSU.

So will it run with a 550W? Sure. I wouldn't. General rule of thumb - get the best PSU you can afford. Cut corners somewhere else. Especially if you plan on overclocking. The most frustrating computer problems I have had to troubleshoot were because of faulty or underpowered PSUs.
 
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yeah no kidding, most PSU's gain efficancy as the load increases but it pretty much flatlines after 40-60% load, so you want to load your PSU in the 40-60% range most of the time to be the most efficiant.

One more thing to consider is fan noise, as the load and heat increase the fan will spin up more and make more noise. I got such a large PSU so that at idle the fan is so slow i cant even tell its on and even gaming it hardly spins up. According to my UPS my system draws abour 300W idle and 500W gaming, my 4890 is a pig at idle. This also give me room for expansion if i decide to go CF. I use a Corsair 850TX PSU.
 
IMHO psu and case is something you will keep rather longer than the rest of the parts of a pc. So I think nothing wrong to invest some money there and also have a little head room.

I only have a i7875k and a 5850 and went for a 700w psu. The one i choose had a review here an AT and the 600w and 500w models were not more efficient even at low loads (200-300w), only cheaper. So I went with the 700w model. headroom for xFire.
 
Rifterut said:
yeah no kidding, most PSU's gain efficancy as the load increases but it pretty much flatlines after 40-60% load, so you want to load your PSU in the 40-60% range most of the time to be the most efficiant.

One more thing to consider is fan noise, as the load and heat increase the fan will spin up more and make more noise. I got such a large PSU so that at idle the fan is so slow i cant even tell its on and even gaming it hardly spins up. According to my UPS my system draws abour 300W idle and 500W gaming, my 4890 is a pig at idle. This also give me room for expansion if i decide to go CF. I use a Corsair 850TX PSU.
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So, pretty much the same goal I stated, just different reasoning. Aim for load to be 50% PSU rating...right? I just had the logic for doing so wrong...must've read it somewhere.
 
Look what I'm running with an HX650, and it's never hiccuped once. If you get a decent PSU it'll run at it's rating, while under load, without any issues.

So, pretty much the same goal I stated, just different reasoning. Aim for load to be 50% PSU rating...right? I just had the logic for doing so wrong...must've read it somewhere.
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It's up to you, but that's pretty wasteful, as far as your wallet goes. Just figure out what you need, in watts and the 12v rail(s), and then buy the PSU that's the next step higher. (ie. if you need a 550W, buy a 650 or 700).
 
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if it helps at all I just plugged an old 480w PSU to run Phenom X4 @3.5Ghz, 2 HDDs, 1 opitcal, 2x2GB, 3 fans and a 8800GT

Everything is just perfect with that.
 
Homerboy said:
if it helps at all I just plugged an old 480w PSU to run Phenom X4 @3.5Ghz, 2 HDDs, 1 opitcal, 2x2GB, 3 fans and a 8800GT

Everything is just perfect with that.
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manufacturer and reliability play a role.

I remember getting an aspire 550w which most people said was garbage.

I still did it anyway to power a core 2 duo and x1900XT, and it ran just fine for months and months. Eventually I deconstructed the system and sold all the parts in prestine condition.
 
I've had a similar setup with a Core i7-920, GTX 260 Core 216, and Corsair VX550. So I'm speaking from experience.

You will be fine if you keep your system at stock voltage, not so fine if you decide to increase the v-core on the cpu/gpu.

P.S. How many fans?
 
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So am I commiting a sin by using Hiper 580R V3 to power a 920 D0 @4.0Ghz, 6gb Gskill (3X2gig) @1916mhz 8-8-8-24, XFX 5770 ZNDC (highest clocked one) + 2-1TB Samsung HD103SJ, SATA DVD burner...

😕


Suggestions on a better PS...?
 
Bartman39 said:
So am I commiting a sin by using Hiper 580R V3 to power a 920 D0 @4.0Ghz, 6gb Gskill (3X2gig) @1916mhz 8-8-8-24, XFX 5770 ZNDC (highest clocked one) + 2-1TB Samsung HD103SJ, SATA DVD burner...

😕


Suggestions on a better PS...?
Click to expand...

don't hijack the OP's thread. make your own.
 
leonlee... Considering he hasnt posted in the thread for over 10 days I dont think its to far beyond a dead post... So meyow meyow... 😛
 
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