Looking for a quiet, high performance, SLI power supply

Hello, I am currently looking for a high performance, but quiet power supply, that can handle SLI.
My current rig is:

Core Components:
ASUS A8N-SLI Deluxe
eVGA Geforce 7800 GTX (In SLI)
OCZ Titanium 2GB (2 x 1GB) 184-Pin DDR SDRAM Unbuffered DDR 400 (PC 3200) Dual Channel Kit System Memory (2-3-2-5)
AMD Athlon 64 X2 4800+
Creative SB Audigy 2 ZS (WDM)

Storage Components:
1x Seagate Barracuda 7200.7 SATA NCQ 3Gb/s ST160827AS 160GB 7200 RPM SATA Hard Drive
2x Western Digital Caviar SE16 WD3200KS 320GB 7200 RPM 16MB Cache SATA 3.0Gb/s Hard Drive (RAID 0)

I have done a bit of research, and found two viable power supplies.
I am wondering, from all you experienced folk, if these power supplies are good and (importantly) quiet?
SeaSonic S12-600 ATX12V 600W Power Supply 100 - 240V UL, CE, CB, FCC
http://www.newegg.com/Product/Prod [...] 6817151025

ENERMAX Liberty ELT620AWT ATX12V 620W Power Supply 90V~265V (Auto Adjusted) UL, cUL, TUV, CB
http://www.newegg.com/Product/Prod [...] 6817194004

However, I noticed the enermax has "Yes" for SLI support, but the seasonic has a "NVIDIA SLI Certified", does that mean the enermax is not SLI certified? I also have read reviews in both power supplies that it's either good, or DOA/explosions.
My budget for this power supply is a little bit more loose than usual, about 250 (USD) Max.

Thanks all

I recommend the Seasonic S12 600. I personally have the S12 500 and it is very quiet. In fact, I can hear other components of my PC, but not the Seasonic S12 unless I really concentrate.

I heard the PC Power and Cooling PSUs are the best on the market. A friend of mine has this PSU, and it's quite loud. Is it possible to take the cover off the psu, and replace the fan with a case fan that is quieter? Or is the airflow needed for safe operation? If so, am I able to put 2 fans to faciliate airflow across the parts inside this PSU, keeping the sound to a minimum?

just to clarify, 2 fans meaning one in the back sucking air out, and one on the front, sucking air in.

Thanks for the replies too.

I have the SeaSonic S12 600w in SLI and it works great AND sileint as far as PSU's go.
CErtified means that it has been ACCEPTED by NVIDIA as a power supply that will meet the power needs of a puter with SLI as well as other peripherals
Heres what I got and YOU tell me if I the 600 W is good enough
HOpe this helps bro


RIG specs
Antec P180 PerformanceSeries Mid-Tower Case
SeaSonic S12 600 watt power supply
Asus A8N32 SLI mobo AMD N-Force 4 SLIX16 (bios 1103 V02.58)
RealTek 97 onboard digital 5.1 Surround
AMD Athlon 64 X2 4800+ Toledo Core, 2 X 1mb L2 cache (AMD driver 1.3.1.0 w/MS hotfix)
2 gigs of Corsair TwinX3500LL Pro @ 437Mhz 2-3-2-6-1T
2- BFG Tech 7900 GT OC 256mb in SLI (nvidia driver 91.31)
Western Digital RAPTOR 74.3 gig 10-K rpm HDD for XP & Apps
Maxtor SATA II 250 G HDD for gaming, movies, MP3's
Maxtor SATA II 250 G HDD for document backup (unplugged)
Sony CD rom 52X
Plextor 708-A DVD/CD rom
Logitech Z-5500 digital 5.1 THX Surround 500watts

Fortrons rails can merge.

I'm pretty sure the Liberty 620 is nvidia SLI certified. But I've got one and it could not power any single high-current GPU that I threw at it, let alone SLI or XFire. I have run XFire with Gigabyte 1900XTs using the OCZ Gamextreme 700 and the mushkin 650. I'm pretty sure your 7800GTX's require less current than the 1900s. The OCZ has a single 12cm fan and the mushkin has two 8's. I was afraid that the 8s on the mushkin would be loud but my ears as well as my dB meter disagree. Both are quieter than my CPU HSFs.

I've heard nothing but good reviews of the Seasonics, so you probably can't go wrong there. I don't know about the loudness of their units. I'd also look at the OCZ, mushkin and FSP units.

Fact is, I am using the very same FSP PSU on my midrange rig when it couldn't handle my highend one and the Silverstone could. I kept experiencing equiptment not being recognized, "new hardware discoveries" and complete inability for video to function when I used the FSP unit. I have an excellent cooling system so I know that heat is not an issue and my GPU has never gone over 38 celsius on load.

However, I have had no issues whatsoever when I switched to the Silverstone PSU. I know the FSP unit is still functioning properly because I still use it, just not on a rig that has as high a demand on the draw.

seasonic all the way, if you can find a quad or tri rail psu with adjustable rails, go for it.

You should put this on your list as well:

OCZ Gamestream 700w

It's always possible that the extra 50 watts of the SST did the trick. I'd have to go back and re-read the reviews, but I seem to remember both of those units delivering on their wattage claims. The SS is rated to deliver 40 more watts on the +12, but both have huge power available (680 vs 720 watts of +12!) and even a peripheral-rich system like yours shouldn't eat that much... I wonder how much the TEC draws? I had problems trying to power eVga 7900GTX's and eventually gave up and switched to ATI. I've read reviews that showed the 1900XT to require more +12 current than the 7900GTX, and I've run two OC'ed 1900XTs on power supplies that wouldn't run a single 7900GTX. Go figger.

Here's a review of Corsairs new PSU by Bjorn3D

http://www.bjorn3d.com/read.php?cID=945

Those calculators are almost worthless, this is what I have:

Athlon 64 3700+
2Gig ram
2 250GB samsung spinpoint sata's
X1800XT 512MB OC'd to 695 CPU and 798 Mem
3 120mm fans
2 DVD burners
Media Reader
Audigy 2
Rhycom 500watt almost-generic psu

It pulls just a hair over 150watts at idle, some network traffic and display is all.

At full load at 1600x1200 with Oblivion maxed it pulls 354 MAX with Amps at the wall of only 3.5.

DC and AC amps are not the same though, but the wattage is a good indicator, just take into account some loss, a good 400 would be enough for my system.

I do realize that the calculations are not accurate but it does help me make some decisions. I know that my FSP 700 (which is still functioning fine in another rig) couldn't handle my setup as I was having intermitten equiptment loss and recognition and my graphics card was going nutso so I went with a slightly more powerful PSU and everything is fine.

I err on the side of caution and always like to give myself some breathing room for future proofing (such as with the newer GPU chips coming out soon). Like it said in the movie New Jack City: "F&*( it, it's my money"

I agree with going over what you need, just saying a high quality 600 for example couple outperform a mid quality 800, watt's don't matter, just the quality.

It is possible to mod it but if you want to keep your warrantee you can have PC Power and Cooling do it for you. The only problem is that you have to order it direct for this to be done.

the seasonics is a fu.cking great PSU.

really stable voltages and can deal with high loads. also whisper quiet. aska make good PSUs too.

Yep, no denying that!!!!

Cool. Like I said, I spoke to them in April. Apparently, they have changed their options - or else the engineer and I missed it back then.

Great choice Q,
I also have the SeaSonic S12 600watt and I have had NO probs with it.
What case are you going to put it in?


RIG specs
Antec P180 PerformanceSeries Mid-Tower Case
SeaSonic S12 600 watt power supply
Asus A8N32 SLI mobo AMD N-Force 4 SLIX16 (bios 1103 V02.58)
RealTek 97 onboard digital 5.1 Surround
AMD Athlon 64 X2 4800+ Toledo Core, 2 X 1mb L2 cache (AMD driver 1.3.1.0 w/MS hotfix)
2 gigs of Corsair TwinX3500LL Pro @ 437Mhz 2-3-2-6-1T
2- BFG Tech 7900 GT OC 256mb in SLI (nvidia driver 91.31)
Western Digital RAPTOR 74.3 gig 10-K rpm HDD for XP & Apps
Maxtor SATA II 250 G HDD for gaming, movies, MP3's
Maxtor SATA II 250 G HDD for document backup (unplugged)
Sony CD rom 52X
Plextor 708-A DVD/CD rom
Logitech Z-5500 digital 5.1 THX Surround 500watts

I've ordered an Enermax Galaxy as my next PSU upgrade so I think I'll be fine for awhile after it arrives