Ragheed

Right now I'm using a Cooler Master 550W, and have a couple of issues.

First, the PSU's fan is too close to the back of the case, so about a third of it isn't directly getting air through the bottom filter. I'm hoping I can get by with this PSU until I need a bigger one (I'm only running one video card right now), but as part of the grill is being pressed onto the frame at the bottom of the case (the one the filter slides under) there is some rattling and the fan might be spinning faster due to less-than-ideal air intake.

I tried mounting the PSU with the fan facing up (using only 3 screws) but that made the rattling much worse.

Also, I'm having trouble routing the 24-pin cable behind the motherboard tray--the right side panel won't always close easily.

At any rate, eventually I want to get that PSU out of there.

A couple that I'm considering for when the time comes to replace it:

Ultra X3 1000W

Corsair 1000HX

Xigmatek 1200W (there's barely any price difference between 1000 and 1200W)

I'd prefer the Ultra or Corsair, with their flat cables that are easier to route behind the motherboard tray. The Ultra seems to be longer so might be a better fit, but if If I'm not mistaken the Corsair has better stability and efficiency (but divides into two 12V rails whereas Ultra has one huge rail). Do the Corsair's cables stay bent any way you want them like Ultra's "Force Flex" cables?

The Xigmatek offers a good value (and has good reviews), and while having 1200W may seem like overkill (I'll probably never use more than two video cards) I might decide to try out extreme cooling at some point. But again I might run into a problem trying to route the 24-pin cable behind the motherboard tray since it's not flat.

What do people (especially fellow Cosmos S owners) suggest?

Edit: I'm hoping whichever PSU I get won't be heard over the case fans. I want my system to be as quiet as possible.

Oh, and thanks in advance.

dragosmp

I don't have a Cosmos S, so I'll keep it short. The Ultra is just not good, the ripple of the +12V rails is too much. It can power your stuff, but the EM interference may brick your OC attempts. I'd say to go for the Corsair which seem to make quality PSUs, or even for a PC P&C Silencer 1000w that is more than appropriate for the geometry of your case.

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Ragheed

Thanks. I read an Anandtech review of the Corsair and they said it's one of the most stable PSUs they've tested.

As for PC P & C, they seem way too expensive once you go above 750W. They say "you get what you pay for," but are they really that much better than everyone else?

dragosmp

I would place the PC P&C 750W on the same level as the Corsair 1000W in the sense that it has higher quality, but lower max power output. If you need 750W+ the choice is clear, the Corsair.

The PC P&C are better in a sense, but there are rare the cases where you really need that quality. They are sort of built to last, kinda like professional PSUs (if such a thing exists).

For me and my rig, the price of a PC P&C is not justified by the higher quality because I don't manage to push even the 580W PSU I currently own. The limit of the power circuitry per phase is around 8-900W on high quality components according to my colleagues that design such thingies, so in order that the P&C 750W to supply such clean voltage in is mandatory to be very high quality, something that is rarely sold for consumers (hence the price). 800W+ PSUs need two phases, thus to make a 1000W PSU you don't necesarily need high quality components, you can just make it from 2x500W/phase - here the only problem is proprer cooling.

From a designer standpoint I like the P&C, I wouldn't think of buying anything else for the 750W level and also for the 1400W-1500W level, but in between there may be acceptable alternatives, provided good cooling is assured.

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Ragheed

Thanks again.

I don't always leave the computer on so the PSU should last a while anyways. I probably won't ever max out 1000W either.

I thought about PC P&C's 750W along with Corsair's 750W, but they're both too small for the case (I really wish CM had allowed for the frame above the filter to be adjusted somehow), and I'd like to have at least the option of running two graphics cards along with a good watercooling system with plenty of fans.

The PC P&C units also have the problem of not having a large fan that would pull air in from under the case. One of the main things that attracted me to the Cosmos is being able to keep the PSU's airflow separate from the rest of the system. That way it'll never compete with the graphics cards for fresh air, or if I watercool the whole system (aside from the PSU--this is way too rich for my blood), I won't have to worry too much about the airflow inside the case, and can go all out with 1/2" tubing and maybe use more than one radiator.

Mmansueto

i have the Ultra x3 and i have never had any issues with it. i have a stable OC at 3.6.

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poohball

I will go with Xigmatek but the 1000W instead of 1200W big rebate going on and is pretty much same unit as corsair.

shinji2k

The Ultra only has ripple problems on the 5V rail and only when it isn't loaded very much. Under normal usage ripple won't be a problem. And even if ripple was out of spec on the 5V rail, it would have nothing to do with how well you can overclock. The only things run off the 5V rail are the logic boards on HD and optical drives and USB. Ram is run off 3.3V and everything else is on the 12V. So ripple problems on the 3.3V could affect ram overclocking and life span and ditto for the 12V rail and gpu/cpu/mobo.

That said, at the current prices for the Ultra you would be better off going with the Corsair or the Xigmatek since they are the basically same PSU on the inside (CWT PUH) and provide more power and are slightly better performers than the Ultra.

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Ragheed

Thanks, everyone.

It's been settled now that I got in on the deal Buy.com had on the Corsair 1000HX: $161 shipped!

It's funny how these things happen, as I was already leaning strongly towards the Corsair, and probably would have bought any one of the three at that price, but I got the exact one I wanted.