SPCR

Can anybody comment about the relative noise level of Corsair's big PSUs, i.e. the 750W+ models? I have two HX620s and an HX520, and I'm very pleased - but I'm building a "quieter" system that has a lot of performance parts, including a QX9650, 4GB of RAM, and a pair of 8800GTS-512s in SLI. HX620 might be adequate, but if the bigger ones are nearly as quiet, I'll prefer the headroom. Anybody have any experience with them?

You'll already have a lot of headroom with the HX620. (qx9650:max. 100W, 2x 8800GTS: max. 200W, ram: 10W, mainboard: 50W, maybe, disks: 10W each).

So my advice would be to be happy about 300-400W of headroom when idle and 200-300W when stressing. It is impossible that you come even close to the limit the HX620 has with this system.

I think you're being a bit too conservative in your estimates of power draw. The TDP on a QX9650 is 130W, the documentation for the 8800GTS-512 says 150W each. But it does look like the 620W can handle this system, even stressed, making me wonder about the upcoming HX1000. I know most systems are vastly overpowered, but OTH I have built a system that drew more than an Antec NeoHE could supply, so it certainly is possible.

In any case, close reading of Corsair's web site says that the TX750 is not quiet at all. It can go to 43dB.

The QX9650 consumes about 90W at full load according to X-bit Labs. It is rated at 130, but never reaches it.

As for the G92 GTS, The Tech Report set up systems that with a G92 GTS took 238W for the entire systems. If you guestimate that the systems alone take about 115W without graphics cards, that means that the GTS takes 120W max. That means that taking the rated watts may lead to a 100W overestimation in power.

I can't comment on the HX line, but TX650W is generally quieter than TX750W.

Oscar wrote:I can't comment on the HX line, but TX650W is generally quieter than TX750W.

I think these quotes might help a bit. "Redbeard" is a Corsair Rep so its the semiofficial word.

Redbeard wrote:The manufacturer breaks down like this:

VX450 - Seasonic
VX550 - CWT

HX520 - Seasonic
HX620 - Seasonic

TX650 - Seasonic
TX750 - CWT

The TX650 is based on a revision of the S12-II design from Seasonic, with some small component changes and our own cable config (longer cables, fully sleeved, more connectors, etc).

Redbeard wrote:The TX650 is kind of designed to be a less expensive HX620 for people who don't care about or want modular cables.

And don't get me started on why the HX is 620W and the TX is 650W. You wouldn't believe how many meetings I've been in where that question gets asked.

Oh and if configurators are your thing there is http://www.corsair.com/psufinder/default.aspx

When I ran it for your system I chose:

Core 2 Quad
8800 GTS x2
1 hard drive
Overclocking the video cards

and the recommendations were 620, 650, and 750.

Thanks for the clarification. I'm going to go with another HX620.