What would my Desktop draw for power? (estimated)

[jacktesterson]

I know I have way too big of a PSU in my desktop, but I recently made a trade for one. It's not actually here yet, but I updated my sig.

I traded a 64GB SSD, MW3 for PS3, HD 6450 Video card and a little cash (mostly to cover shipping expenses to me in Canada) for a Kingwin 1000w 80 Plus Gold Modular Power Supply over at Hard Forum. It was a good deal for both of us as we traded unused items for things that will be used.

I was running an older model Enermax NAXN before, that was not 80 plus certified. It is normally just my backup PSU I keep in the house.

Anyways, since I could trade for it, I took it.

Any idea what kind of Wattage my System may draw? Will my PSU still run half what efficient at the lower wattage?

My CPU runs at 1.28v

 

[XFX Support]

I would estimate that the system listed in your profile would draw in the low 400s, possibly 500 depending on how well your CPU handles that overclock. According to 80plus.org, that PSU runs at about 90% efficiency in that range.

 

[lehtv]

Not sure where the XFX rep gets those numbers. 2500K @ 4.4 probably uses around 150W or less, the 7850 uses only 110W. Consumption well below 300W during gaming. If you stress tested with prime95 + furmark simultaneously you'd go past 300W. A 550W PSU would be more than enough, even 430W would handle the system fine. And your Kingwin would handle 7850 quadfire without breaking a sweat.

 

[ElFenix]

you'll be into the efficient part of the curve when loaded but i bet that system <100 watts at idle.

 

[The Wayfarer]

You could always buy an electricity usage monitor, like this:

http://www.newegg.com/Product/Produc...82E16882715005

They're pretty inexpensive.

 

[bononos]

..... Any idea what kind of Wattage my System may draw? Will my PSU still run half what efficient at the lower wattage?

My CPU runs at 1.28v

Have you looked into online power supply calculators? You can adjust the cpu speed to estimate how much the power the entire pc takes on idle or overclocked. The alternative is to buy a device like the link given above.

The efficiency of 80+ certified psus is tested at 20%,50%,100% levels of power output so your psu is good unless you're running it at something like 5% of its rated power.

 

[ElFenix]

Have you looked into online power supply calculators? You can adjust the cpu speed to estimate how much the power the entire pc takes on idle or overclocked. The alternative is to buy a device like the link given above.

nearly all of them seem to overestimate by at least 50%

 

[wpcoe]

According to the Thermaltake online estimator for what I anticipate on my next system (Ivy Bridge i3, no video card (only IGP), 4 RAM DIMMs, one SSD, two green HDDs and a DVD, plus a couple USB devices and a PCI modem) it advised 230W. If that is overestimated by at least 50%, then the actual would be about 150W?

I used a few specs on the higher side, like entering two SSDs, had to select Sandy Bridge (since Ivy is not a choice yet), added a card reader, extra case fans, etc.

If the real power draw is ~150W, then I could go with a 400W PSU with *large* cushion for degradation???

 

[TemjinGold]

With no video card, you would only draw ~150w near peak. Real world day to day draw on average will be more like 50w.

 

[ElFenix]

i'm fairly confident that the real power draw of an i3 like that at load is going to be under 100 watts from the wall. my athlon 630 at load with 2 green drives draws about 115 watts, and that's with using a pci-e video card (granted, a 7300LE), no SSD (but they don't draw much), and no modem. USB is negligible (current spec is 2.5 watts draw).

 

[TemjinGold]

Haha I should clarify: I meant to say, without a video card, the only way he could draw the 150w mentioned is at peak. Not that he will actually draw 150w at peak.

 

[dualsmp]

Your system would easily run on a smaller 450w PSU. 1000w won't run as efficient when idle but it might only be a 10 watts or less wasted.

 

[jacktesterson]

I eventually am stepping up to a 1080p TV (60" +) and Crossfiring my 7850.

I know 1000w is overkill, but like I said, I traded for it, so I can't complain.

I always have preferred to use a TV over a Monitor for gaming.

 

[TemjinGold]

The TV will make no difference for your PSU. Crossfiring your 7850 means you should have a 650w unit and that's already plenty of headroom. 1000w is a huge waste. You may actually do better by selling that 1000 watter and buying a nice 650w instead. You'll pocket some nice change (much of what you'd need to crossfire that 7850 in fact!)

 

[Concillian]

~ 100 W idle 200-250 gaming is my guess.

A kill-a-watt is like $25 and you don't have to guess.

You really would want a 500-650W supply to be in the meat of the PSU's efficiency curve at expected loads.

 

[jacktesterson]

The TV will make no difference for your PSU. Crossfiring your 7850 means you should have a 650w unit and that's already plenty of headroom. 1000w is a huge waste. You may actually do better by selling that 1000 watter and buying a nice 650w instead. You'll pocket some nice change (much of what you'd need to crossfire that 7850 in fact!)

haha. I know the TV makes no difference. My point was I'm upgrading to a higher Res soon and eventually will be adding a 2nd card for that res.


I know its a huge overkill. I was just wondering what the efficiency will be like on a big gold rated PSU like this at low draw.

 

[Concillian]

Gold PSUs are typically
~81-83% range at 10% draw
~87-88% at 20 %
~90%ish from ~30-70%

There is some deviation supply to supply, but in general this is what you can expect to see. So if you're using no more than 400W, a 1000W supply gets you headroom at the expense of ~5-10 watts vs. a smaller supply that better fits your usage profile.

 

[TemjinGold]

The issue is that he will be at 5% draw on idle with the 1000w, where the efficiency falls off a cliff. In any case, it won't be a huge difference in actual watts. Where you are losing is that you are essentially losing the price difference between that PSU and one that would better suit your needs and you gain nothing for it. Do note that the 650w I mentioned would be more than enough for AFTER you add your 2nd card.

 

[jacktesterson]

Would it really be worth selling it?

 

[TemjinGold]

You'd pocket ~$100 - $150 if you sold it and bought one of those XFX 650w units that lehtv loves. You decide if that's worth it.

 

[jacktesterson]

I bought an OCZ ZT 550w power supply for $34 shipped from eBay (tiger direct) using ebay bucks to bring the price down cheap. it has good reviews and is modular. I'm going to sell the kingwin for profit.

im happy with a single 7850 too.