PSU calculator

[Psi*]

I never know how much excess that I am buying, and always hope that I am getting some excess but I refuse to go over $200 for a PSU.

I came across this in overclockers Australia.

I have seen calculators on the net although lately not too many have been kept up to date. This has the latest quad core Intel & AMD CPUs in its database.

 

[2Tired2Tango]

I came across this in overclockers Australia.

Very handy. Thank you!

 

[gibbersome]

Awesome tool, thanks Psi!

 

[Rob Williams]

PSU calculators in the past were horribly inaccurate, but I put my current hardware configuration through this one and the result was 383W, so it seems fairly realistic. What I find ironic is that a calculator like this is likely to hurt Thermaltake sales more than help. I am running a fairly typical enthusiast machine, and it tells me I only need a ~400W PSU... Thermaltake is trying to push models that go 800W+.

Coincidentally, I did purchase a 400W Thermaltake PSU about a year ago for my mother's PC, and it's been stable as can be.

 

[Doomsday]

pretty nice! Corsair have one one theirs too but it only recommends their power supply!

 

[2Tired2Tango]

PSU calculators in the past were horribly inaccurate, but I put my current hardware configuration through this one and the result was 383W, so it seems fairly realistic. What I find ironic is that a calculator like this is likely to hurt Thermaltake sales more than help. I am running a fairly typical enthusiast machine, and it tells me I only need a ~400W PSU... Thermaltake is trying to push models that go 800W+.

Coincidentally, I did purchase a 400W Thermaltake PSU about a year ago for my mother's PC, and it's been stable as can be.

There are advantages to going "overkill" on power supplies, Rob. The most obvious one is heat... an 800w supply operated at 40% capacity is going to run cooler and last longer than a 400w one operating at 80%.

Please recall our previous conversation about how "watts" aren't simply watts. The distribution of that wattage also matters... some will have more power on the 5v line less on the 12, others will favor the 12 and skimp on the 5... so there's more to the decision about supplies than just adding up average power consumption. Then there's the question of "Who actually makes this stuff?" as most often the OEM's specs will be more accurate than those of a rebrander.

A really good calculator would tell you how many watts you need on 12v, 5v, 3.5v etc. as separate values so you can make a more informed choice.

 

[Kougar]

Oh wow, that is hilarious!

This used to be a pay-only PSU calculator (with a cut down, lite version for free) which one could find at: http://extreme.outervision.com/psucalculator.jsp

What is funny, is they appear to have licensed it out to the various PSU makers... Antec also has the same one.

Newegg has a much simplified version of their own as well: located here.

Generally when PSU shopping, one's going to want 20% more on the PSU wattage anyway. Not because of headroom (that's a good reason in of itself), but because 80% loads are generally the most efficient. Anything lower or higher means the efficiency rating goes back down, and quickly on cheaper models.

I tested the free "lite" version of the PSU calculator a few times in the past (It's been around for over 3 years) and it was reasonably accurate with my Q6600 system especially with my high overclock settings, which I found to be surprising.

 

[Rob Williams]

There are advantages to going "overkill" on power supplies, Rob. The most obvious one is heat... an 800w supply operated at 40% capacity is going to run cooler and last longer than a 400w one operating at 80%.

Of course. That seems obvious to us technical folk, but for few people using these calculators are going to take things like this into consideration. It's interesting logic, though, because it pretty-much would debunk the need for this calculator at all. Just purchase a big PSU and be done with it.

A really good calculator would tell you how many watts you need on 12v, 5v, 3.5v etc. as separate values so you can make a more informed choice.

Definitely. That would be very, very difficult to pull off (in the time-consuming sense).

This used to be a pay-only PSU calculator (with a cut down, lite version for free) which one could find at: http://extreme.outervision.com/psucalculator.jsp

Yes... that's the one I was referring to in my original post. It was horribly inaccurate, but it's gotten a lot better it seems.

 

[Psi*]

I just came across a reference to this ASUS power supply calculator.

It does not ask for enough information to break out power requirements by voltage bus. I haven't compared to the other calculators as yet, but this one is pushing the higher wattage PSUs, 750+ watts, that I wasn't planning on. It does let me select the latest ASUS m/bs & I plugged in the P6X58D, all I7s show as 130 W. I have read that typical over clock wattage is pushing 200 W ... so add on another 70 W for that. Add, 6 sticks of RAM & just one good video card bumped up power to 750 W.

I don't expect 2 video cards, although a GPGPU is not far fetched. I need to consider a ludicrous1000 W PSU! That will be more than $200.

 

[Rob Williams]

I just came across a reference to this ASUS power supply calculator.

It does not ask for enough information to break out power requirements by voltage bus. I haven't compared to the other calculators as yet, but this one is pushing the higher wattage PSUs, 750+ watts, that I wasn't planning on. It does let me select the latest ASUS m/bs & I plugged in the P6X58D, all I7s show as 130 W. I have read that typical over clock wattage is pushing 200 W ... so add on another 70 W for that. Add, 6 sticks of RAM & just one good video card bumped up power to 750 W.

I don't expect 2 video cards, although a GPGPU is not far fetched. I need to consider a ludicrous1000 W PSU! That will be more than $200.

A 1000W PSU isn't needed at all... 700W or 800W tops. It's important to get a good-quality model from a respected brand though... it's not something you want to skimp on. 1000W is a bit overkill for almost all high-end setups, though.

 

[eunoia]

Re: ASUS

Page 2-39 of the manual for the ASUS P7P55D Premium manual states: "If you want to use two or more high-end PCI-E x16 cards, use a PSU with 1000W power or above to ensure system stability."

I thought that was kinda funny when I read it.

 

[Rob Williams]

Page 2-39 of the manual for the ASUS P7P55D Premium manual states: "If you want to use two or more high-end PCI-E x16 cards, use a PSU with 1000W power or above to ensure system stability."

I thought that was kinda funny when I read it.

Well, oddly enough, our friend Nate at Legit Reviews hit over 1000W power draw on a machine he was testing the other day, single-CPU and dual-GPU setup, and nothing else much special about it. He wouldn't mention what GPUs he was using, though.

 

[Kougar]

Sounds like a dual dual-GPU setup to me... then again if he was overclocking the crap out of it in a freezing room I can see two single GPU's and a Core i7 easily hitting 1,000W draw from the wall. My own rig can pull over 700W from the outlet according to my own power meters, and it's just a measly GTX 260.

 

[Rob Williams]

Yes, I'm sure it was a dual dual-GPU setup, and he swore he wasn't overclocking. Still seems high to me, though, because even two HD 5970's shouldn't be able to push the power that high (perhaps I'm wrong).

 

[Kougar]

I could hit >700W with just a Q6600 at ~3.8GHz and 8800GTS 320mb, as measured with a P3 power meter. Sure if you factor in PSU efficiency the actual PC power consumption would be about ~15% below this figure, but it doesn't surprise me at all.

Overclocking can more than double a system's power draw... factor in four drives in RAID, a DVD burner playing a CD, soundcard, overclocked FSB bus and overvolted RAM, FSB, MCH, CPU... about 12 120mm fans, and another 40W for the water pump, then it's quite doable indeed.

With two 5970's I bet I could make 1,200 watts look like small potatoes.

 

[Rob Williams]

With two 5970's I bet I could make 1,200 watts look like small potatoes.

And that's just insane... imagine how much that would increase the power bill, seriously. I remember back when I ran Skulltrail for a month prior to our launch article, and I noticed the difference in the power bill. I could imagine one of these 1,000W+ Goliath's.

 

[Kougar]

Thankfully, that is why I live in a city with municipally owned utility companies. (Okay, more like it was random luck) The electric rates are half of those an hour's drive north of here.