New PC build PSU

I have bought 3 or 4 Seasonics (330 watt to 550 watt, Bronze 80+) over the years, and are happy with them. They are efficient and quiet, though after 5 years the fan on one did get a little noisy at full load, but that is to be expected. And they do work at the rated load, unlike the cheaper brands.

But I have now standardized on the Rosewill 80 Plus Gold from Newegg; they are even more efficient for the price, and are frequently on sale. I have just had them a year or so, but no problems thus far.

No argument at all with that. The biggest problem is that unless you really research things properly, you could (in your eagerness to get going) end up standardising on something not quite as good as it could be. To choose properly you need experience and to get your own experience you need to choose :-). In other words, take plenty of time to research and think things through.

Come on now, there are plenty of good hardware review sites out there to point you in the right direction. It's not the quality of information that's the problem, it's the time to consume it :-).

As archae86 says, good brands (like seasonic and others) that manufacture their own product rather than rebadging that of someone else, are preferable. You should trawl through lists like this one (just as an example) and get some idea of how models you might be interested in really do perform. If you study the full articles in detail you can get a lot of good information to help you choose.

Why? You should configure a machine first and work out how much power it will use. PSU's usually work at their best efficiency if they run at around 40-60% of rated load. So your best choice is likely to be a high efficiency unit that is rated at around 1.8X to 2X your design load. Without knowing your design load, it's a bit hard to make a proper choice of PSU. You really should choose the PSU last, once you have worked out what you want to put in a machine.

Your biggest choice is probably what GPU you will use and how many you will install per machine. You should really think that through very thoroughly before worrying about a PSU. You need to properly consider that Einstein GPU apps tend to be hungry for PCIe and memory bandwidth. It might sound like a good idea to invest in a multi PCIe slot board and load it up with high end GPUs, but unless you are very careful with your choices, the performance may be quite sub-optimal.

I'd be very much the wrong person to advise you about that since I don't run any multi-GPU hosts. My design choice was to use single slot budget boards and to keep well away from the high end (power hungry and expensive) GPUs. So all my machines have a single, mid-range at best, GPU. The motherboards cost around $50 and the GPUs around $130. With an i3 type CPU, I get well over 70K RAC per machine. These hosts draw well under 200 watts from the wall and each one has 2x175W PSUs, one powering the motherboard and one powering the GPU.

I've built quite a few machines like this over the last 12 months or so and they run very well. The PSUs actually were built in 2002 and I acquired them in around 2007 when I bought over a hundred machines at around $10 each at a computer auction. The machines had Tualatin P3 CPUs (just before the P4s were launched) and had P4 capable PSUs with around 100W 12 volt capacity. They seem to be perfect for powering an Ivy Bridge or Haswell i3 these days. I've not had any of these PSUs fail, even though I ran the original machines on this project for a couple of years after I bought them.

High strength, steel (very heavy) 4U server cases - I'm glad it's you who'll be manhandling them!! You need something small and light that you can leave open for ventilation. Extra fans draw power. You need to design for natural ventilation if possible. When I can, I'll post a picture of a case setup that works very well for me.

Good luck with your research - you really should take the time to do it.

All mine are Seasonic. Some 500w, some 750w. I could actually downsize the power supply a bit on the machines without GPU's as they don't need 500w but I recycled them from some Q6600 boxes as I upgraded. Haven't had one of them fail yet. Currently have 10 i7's in the farm.

I also have a Corsair 1000w that I use from time to time, its a few years old now and hasn't missed a beat.

I prefer to get modular power supplies as you don't always need so many PCIe and SATA power cables in each machine and keep the spare cables for when you change things around.

How did you come-to the number 10?

Is that the amount of rack-space you have available, or is there some other measure at work?

The good power supplies are almost always immediately identifiable by price, unfortunately.. You didn't really indicate a desire to save money, so if money is no object, find the expensive stuff and buy it.

This conversation gets a little weird. You said that these machines (or at least the cases) will be in service for many years.

It is, in my current estimation, a mistake to buy a lot of armored top-flight equipment capable of repelling the barbarian hordes because it'll likely be outdated before it dies.

Brands? I have recently stopped buying new PC Power & Cooling power supplies. Well, it feels recent to me. The company was bought-out by another company that started re-branding lesser units and has gone bankrupt, themselves. Yet another company has recently acquired the brand. Any good? I don't know.

Why mention this? Well, if you'll go look at their website and look in the "buy direct" area, you'll find refurbished units for sale for very reasonable prices. The venerable Silencer 750 Quad can often be had for $80-90. Those are the "style" that PC Power & Cooling produced when they were the cat's meow and commanded a high price premium. (back before the Earth cooled)

While my personal experience with these specific refurbished PSUs is very good, I'm not suggesting you do the same. In fact, I suggest you don't. I don't think they have enough fan capacity in your situation.

What I am saying is that sometimes you can get bargains if you are bargain-hunting by knowing where to look.

Unfortunately, in addition to my five or six old Silencer 750 Quads I also own three of the PC Power & Cooling "Silencer Mk II 950w" power supplies from OCZ and two of them have-had to go back for replacement, and recently I received a replacement that was DOA that had to go back yet again. Those were purchased "new", no refurbs. In other words, PC Power & Cooling isn't what it used to be.

The point being that a "brand" doesn't mean much when manufacturing facilities are changed, ownership changes, QC changes, design changes, etc. So unless you are buying all of the power supplies for all ten machines *right now* whatever you decide is best now may not be by the time you decide to build numbers 2-10.

I trust JONNY GURU, I wish I had read his review of the Silencer Mk II 950 before I bought three.

The advice you've already received regarding buying units with the *real* manufacture's name on it is good advice, although I've never followed it. I'm always on the prowl for a "deal."

To quickly replace the last dead Silencer Mk II 950 I bought one of these: [url=http://www.corsair.com/en-us/power-supply-units/rm-series?power=1000%20Watts|]Corsair RM 1000][/url]

I loves me some modular power supply. For reasons I never even took into consideration before, I really, really prefer them. Talk about easy to use. Wow. And you don't have to hide all the useless extra cables you don't need, you just don't use 'em and life is good. I'm not going to suggest you buy what I bought. It's a fairly new "series" and I don't have much history with it.

However, it's an actual suggestion that you look for FULLY modular power supplies when you are shopping. It's much easier to route cables and change things when necessary.

Ok, I accept that you have your reasons and that these cases have their virtues.

I see a potential problem.

Even in other cases blowing 200mm case fans in on the front and having one or more on the sides, one on the bottom, and one or more on the top, it's still challenging to keep multiple GPUs cool. The more powerful the GPUs are, the harder it is to keep the case air, and by extension the GPUs, cool.

While I see lots of potential for getting air into that case and blowing it around inside the case, I'm less thrilled with the provision to evacuate that hot air out of the case.

Because of what I see when I look at the case carefully, I'd suggest you confine your GPU-buying to only those cards with a squirrel-cage type fan at one end that exhausts out of the case at the other.

There are some great cooling solutions out there that don't do this. I've been recently impressed with NVIDIA's new ACX coolers, for instance, but I don't think that's going to work for you.

If hot air is allowed to blow out of the sides of the cards the interior of that case is going to get hot in a hurry with multiple GPUs in it.

I'm not suggesting you do what I've done, I'm just giving you a point of reference. I had a computer in an Antec 900 case which was very happy running two GTX 560Ti cards and a six-core CPU without heat issues, but only after I installed a Corsair H80 closed-loop water cooler and radiator and used two GPUs that exhausted out of the back in addition to a large-fanned PSU pulling air through the case. Only a very small amount of heat was exhausted into the case and it was evacuated by the GPUs, the radiator fans, the PSU, and the fan out of the top of the case.

I ended-up doing that after being unable to adequately cool two GPUs that vented into the case even after the H80 was installed. Those ended-up moving to much larger cases with even more fans.

I'm not sure you even can do the liquid-cooled CPU-route because that case specifies 80mm fans in the rear, not the 120 or 140mm fans that are commonly in cases these days. I'd probably use cool-running CPUs and not crunch on them.

To sum-up, I suggest you get video cards that exhaust out of the case rather than in, and that you don't try to standardize all ten machines at once (instead reading current reviews of what is available). Unless you are going to go from 1 to 10 very quickly, things will change.

And, btw, I don't consider myself some sort of self-appointed expert. I'm just trying to give you the benefit of my experience which is limited only to what I've experienced.