Please satisfy my curiosity - PSU question

[potatochobit]

the efficiency peaks at 80%, derp, MAYBE LIKE IT SAYS ON THE BOX

 

The user has aspirations of adding a second (perhaps third, though unlikely) GTS 250 to bring the total to roughly 450 watts give or take a bit. I suggested that 850 watts was crazy overkill (especially given his current power draw) and he'd be fine with a quality 500-550 watt PSU.

Now, can you please restrain yourself from trolling any more? Acting like we are all completely ignorant isn't helping your argument.

 

Whether you agree or not, 200w+450w is still 650w, the math does not change. That is exactly what I said. I don't know what you are so mad about.

 

I will make you a deal, I will stop trolling when you stop telling people SSDs in raid increase your FPS.

[broooooooce]

Yeah, I just came back to say "Oh, it was you who was arguing with me in that thread!"

 

That said-- Higher wattage does NOT MEAN HIGHER LOAD EFFICIENCY, although it can. It depends.

[Waco]

Whether you agree or not, 200w+450w is still 650w, the math does not change. That is exactly what I said. I don't know what you are so mad about.

 

I will make you a deal, I will stop trolling when you stop telling people SSDs in raid increase your FPS.

Mad? I'm only slightly frustrated that you constantly troll everything. Also - not all PSUs peak at 80% load - and not all PSUs have the efficiency curve on the box.

 

As for your deal - if you get constant frame drops because your computer is waiting on your disks to deliver data (which isn't an unlikely scenario with many games) - fast SSDs will increase your average (and minimum) FPS. So I guess you get to keep trolling since I won't concede a non-fact.

 

 

Yeah, I just came back to say "Oh, it was you who was arguing with me in that thread!"

 

That said-- Higher wattage does NOT MEAN HIGHER LOAD EFFICIENCY, although it can. It depends.

That it was. I agree totally with what you said - I don't know what I was thinking when posting in that thread.

Edited March 16, 2011 by Waco

[broooooooce]

Mad? I'm only slightly frustrated that you constantly troll everything. Also - not all PSUs peak at 80% load - and not all PSUs have the efficiency curve on the box.

 

As for your deal - if you get constant frame drops because your computer is waiting on your disks to deliver data (which isn't an unlikely scenario with many games) - fast SSDs will increase your average (and minimum) FPS. So I guess you get to keep trolling since I won't concede a non-fact.

 

 

 

That it was. I agree totally with what you said - I don't know what I was thinking when posting in that thread.

 

Here is an example for you to consider

 

A machine that draws 200 watts hooked to a 1000 watt PSU is running at 20% of the load capacity, which is at the very low end of the efficiency bell curve.

 

Raising the wattage even more would DECREASE the efficiency at max load even further.

 

However....

 

A machine that draws 200 watts hooked to a 250 watt power supply is running at 80% of load capacity, which is pretty high. Most PSUs tend to get their peak efficiency at 60% or so of their load, so this is on the other side of the bell curve (however, that side is MUCH more forgiving). Hooking that same machine up to a 300 watt power supply would actually put it at 60% load which would INCREASE efficiency.

 

So while it CAN increase load efficiency, it doesn't NECESSARILY. It isn't a linear relationship.

 

That said, most people around tend to use these calculators to figure their MAX power usage if EVERY single component was running wide open 24/7 and then they get a power supply that is rated for much more than even that. While my box probably consumes 400-450 watts if everything is running at full blast, most of the time it's probably only drawing 200-250. So I chose a 560 watt power supply so I'd have a LITTLE bit of room if I wanted to upgrade my video card, so that I could run everyhing at maximum without worries, and so that I'm at least around 40-50% of load 95% of the time-- which still isn't quite optimal, but it's a hell of a lot closer than most of the builds I see these days.

 

Bruce

[Andrewr05]

Or if your 5 year old PSU can even produce the same amount of power as when it was new without failing.

I meant to add that in as well.

 

oops

 

[Waco]

...and so that I'm at least around 40-50% of load 95% of the time-- which still isn't quite optimal, but it's a hell of a lot closer than most of the builds I see these days.

40-50% isn't bad though - PSUs with 80 Plus certification are guaranteed to be at least 80% efficient between 20% and 80% IIRC.

[Gr4vitas]

the other guy who said 70a was correct, the rest of you were wrong.

 

You may not have given out much advice on power supplies lately but I guarantee you that 9 times out of 10 if someone asks should they buy a 650w power supply or an 850w power supply they are talking about the cheapest 39.95$ C-mart brand power supply they can buy.

 

now to put it simply, it is generally accepted that you would get a power supply that is 200W over your need. this ensures some future proofing for upgrades and add ons. some people will even say 100w is enough.

 

so if your friend is pulling 400w at the wall, he needs a 650w supply, an 850w is ludicrous unless he has definite crossfire plans.

 

First of all you are incorrect. Opinions are not fact, therefore nobody can be wrong or right, thusly nobody so far (other than you) has stated anyone was right or wrong. We've only stated our opinion and said "Yea we feel X because Y and Z is really rediculous."

 

Your kind of annoying. No offense.

[broooooooce]

Gr4vitas: I dunno, while it is my opinion that I am expressing, it is an opinion based on quantifiable evidence so you can't really put it in the same league as taste-based opinions, such as blue is prettier than red (it is, by the way).

 

Been reading over this for the past few minutes: http://www.anandtech.com/show/2624/3

 

Also, Waco, you're right. The 80+ PSUs do make the difference somewhat negligible, but in principle I am against waste and inefficiency--regardless of quantity. Also, we can't really assume that everyone shops for 80+. I did a google image search on PSU efficiency curves and anything below 20% drops off DRAMATICALLY very quickly, so you might employ the example I used above of the machine that pulls 200 watts actually becoming terribly inefficient even for many 80+ certified PSUs if attached to a 1200 watt PSU.

[potatochobit]

Your kind of annoying. No offense.

Give this man a cookie! I believe in tough love.

but you need to brush up on your reading comprehension, sugar. You are quoting me out of context. The 'other' people that are 'wrong' are hypothetical people that do not exist from Waco's mock scenario. If you thought I was commenting on a previous post or poster, I was not.

 

Generally speaking, larger PSUs require more electricity to idle but are more efficient under heavy load.₁ *disclaimer* this is just an educated guess.

 

1. all other things being equal

 

Edit:

and it's You're

Edited March 16, 2011 by potatochobit

[Alexandre]

First of all you are incorrect. Opinions are not fact, therefore nobody can be wrong or right, thusly nobody so far (other than you) has stated anyone was right or wrong. We've only stated our opinion and said "Yea we feel X because Y and Z is really rediculous."

 

Your kind of annoying. No offense.

Gr4vitas,

 

It appears that you are confusing subjective truth (truth based on the subject's opinion like "I like vanilla icecream") with objective truth (truth based on an object's properties such as "Insulin will help your diabeties not icecream").

I would also like to point out that you have contradicted yourself by saying "you are incorrect" and then continuing to explain how no one can say someone is incorrect. This is a common mistake that I am seeing more and more nowdays...

 

That aside, I would like to say that I total agree with Waco's and Caxis0's views on this thread's querie and I would actually like to thank Caxis0 for showing me some flaws in my previous recommendations of PSUs I had made a few months back, which I have now rectified.

 

In general, PSUs are most efficient when running under 40-60% load but I would say 50-60% is probably the best region to be in.

 

By buying a ridiculously huge PSU you would be doing a few things which are not desirable:

 

1) Wasting money on a higher wattage PSU for power you will not need.

2) Adding to the power bill due to low efficiency levels - meaning you are wasting more energy - like Caxis0 has pointed out.

3) Increasing case/ambient temperatures due to lower efficiency

4) Wasting room inside your case (a moot point at times)

 

There are many other things than "I want the most power I can get" which should to be considered before buying a PSU.

 

Can't wait to see what Paul has to say on this issue

[Speedway]

Wow, I thought it would only be a matter of time before the grammer police showed up. If I had nothing better to do then point out 1 mistake out of an entire thread, I would find a new hobby!

[potatochobit]

quantity =/= quality

It would have been rude if I had let the opportunity above slide.

now this is off topic and you are going to get me warned for trolling.