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jack bauer

Senior member
Mar 17, 2006
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Don't mean to double post, but the old message got overloaded with replies. I'm looking for a power supply that is quiet, but over 500W if I decide to run two videos cards. My basic system will be: Opteron 170, 7800GT, A8N32-SLI MB.
 

Duvie

Elite Member
Feb 5, 2001
16,215
0
71
I like the OCZ modstream or powerstream 520's....They are reasonably price...I find the fans quieter then most other things on my rig....

I think enermax may have some whisper mode type of power supply...I have seen 470's for sure...
 

Continuity28

Golden Member
Jul 2, 2005
1,653
0
76
Originally posted by: jack bauer
looks noce, would it support SLI?

All of the ones mentioned so far would. Whats most important is the ratings on the 12V rail(s). Remember that the rails aren't additive, so even though one may have 22A + 22A, the total amount is actually 32A... and 32x12=384W on those rails. Lesser power supplies would advertise having 600+W but having it mostly on the 3.3V and 5V line, making it less useful for SLI users.
 

LOUISSSSS

Diamond Member
Dec 5, 2005
8,771
58
91
naw stick with the foolowing brands.. it will be all you'll be hearing about in this forum, antec, fsp, enermax, pcpc, seasonic. i've only owned an fsp so i can vouch for fsp's blue 500watt with 120m fan, i believe they use yate loong quiet fans..
 

BigPoppa

Golden Member
Oct 9, 1999
1,930
0
0
Originally posted by: Continuity28
Originally posted by: jack bauer
looks noce, would it support SLI?

All of the ones mentioned so far would. Whats most important is the ratings on the 12V rail(s). Remember that the rails aren't additive, so even though one may have 22A + 22A, the total amount is actually 32A... and 32x12=384W on those rails. Lesser power supplies would advertise having 600+W but having it mostly on the 3.3V and 5V line, making it less useful for SLI users.

Care to show me how 22A + 22A = 32A? Dual rail PSUs still confuse me a little.
 

Continuity28

Golden Member
Jul 2, 2005
1,653
0
76
Originally posted by: BigPoppa
Originally posted by: Continuity28
Originally posted by: jack bauer
looks noce, would it support SLI?

All of the ones mentioned so far would. Whats most important is the ratings on the 12V rail(s). Remember that the rails aren't additive, so even though one may have 22A + 22A, the total amount is actually 32A... and 32x12=384W on those rails. Lesser power supplies would advertise having 600+W but having it mostly on the 3.3V and 5V line, making it less useful for SLI users.

Care to show me how 22A + 22A = 32A? Dual rail PSUs still confuse me a little.

In this particular scenario, if you load one rail to 22A, the other will only allow 10A to be loaded. Pay special attention to the actual label on the power supply itself. Different brands handle rails in different ways.

Example1 - Enermax
Example2 - SeaSonic

Notice how the rails on SeaSonic are completely additive (18+18=36 36Ax12V=432W) whereas on the Enermax they are not. (22+22=44 But 32Ax12V=384W)

Make sure you know what you are getting by looking at this label.
 

Howard

Lifer
Oct 14, 1999
47,982
11
81
You'll need a PSU with at least 32A off the 12V rail(s). I input your system into the extremevision PSU calculator and upped the power by about 30 watts because the A8N32-SLI takes a lot of power.

See sig if you're still confused.

The Enermax Liberty EL500AWT will handle your system with 2 7800GTs, but won't do anything more than that. If you're looking for more power, the EL600AWT isn't worth it because you only get a total of 4 extra amps off the 12V rails compared to the 500W version. Pretty quiet. Good efficiency, around 80%.

The Seasonic S12-500 can also handle your system with 2 7800GTs (produces 33A on 12V), and the S12-600 also only gives a total of 3 more amps off the 12V rails compared to the 500W version. Pretty quiet... probably has the edge over the Liberty. Good efficiency, around 80%.

The OCZ Modstreams don't have enough power. The Powerstream 520W and 600W PSUs do, but I don't know how quiet they are. Efficiency is low, hovering around 70%.

The Fortron FX600-GLN supplies a ridiculous amount of current (up to 45A or so, I'd say - their specs aren't very clear) and is supposedly very quiet - no idea how it compares to the S12 series. It's relatively inexpensive too - $125 from ewiz. Good efficiency, probably slightly higher than 80%, claimed efficiency is 85%.
 

Zepper

Elite Member
May 1, 2001
18,998
0
0
I ran across a batch of new Enhance units over on eWiz. The 600W unit has aPFC, full-range AC voltage sensing, black, 12cm fan, SLI/PCI Express, and is modular to boot for $97. + shipping. These aren't quite as quiet as the Seasonic S12 series, but considerably less expensive. But the price champ is still the FSP550PLG-SLI at $85. +sh at eWiz. Most of the goodies (aPFC, auto voltage, SLI cert) and Single rail too. Cool beanz!
. With the $$s you save, you can mod the fan in it for noise.
.bh.
 

Howard

Lifer
Oct 14, 1999
47,982
11
81
Originally posted by: Zepper
I ran across a batch of new Enhance units over on eWiz. The 600W unit has aPFC, full-range AC voltage sensing, black, 12cm fan, SLI/PCI Express, and is modular to boot for $97. + shipping. These aren't quite as quiet as the Seasonic S12 series, but considerably less expensive. But the price champ is still the FSP550PLG-SLI at $85. +sh at eWiz. Most of the goodies (aPFC, auto voltage, SLI cert) and Single rail too. Cool beanz!
. With the $$s you save, you can mod the fan in it for noise.
.bh.
Definitely a contender, though efficiency is low and I'm not liking those user reviews on eWiz...
 

JEDIYoda

Lifer
Jul 13, 2005
33,986
3,321
126
The fortrons almost always are the best bang for your buck!!
Also note-- that just becuase your PSU might be SLI Certified that does not mean it cannot handle a SLI set up!!

For example my first PC Power & Cooling PSU the 510 deluxe....no mention of being SLI certified yet...I was told that it would easily handle a SLI set up....from what I understand all I would need is a splitter...

I`m sure if my PSU would handle a SLI set up...there are other brands that are NOT SLI certified that would be able to handle a SLI set up.

Good Luck!!
 

Howard

Lifer
Oct 14, 1999
47,982
11
81
Originally posted by: JEDIYoda
The fortrons almost always are the best bang for your buck!!
Also note-- that just becuase your PSU might be not SLI Certified that does not mean it cannot handle a SLI set up!!

For example my first PC Power & Cooling PSU the 510 deluxe....no mention of being SLI certified yet...I was told that it would easily handle a SLI set up....from what I understand all I would need is a splitter...

I`m sure if my PSU would handle a SLI set up...there are other brands that are NOT SLI certified that would be able to handle a SLI set up.

Good Luck!!
Fixed?
 

Sir Jman

Banned
Dec 16, 2005
211
0
0
read newegg reviews, sort from lowest to highest (I was looking at the 620). Now i know not all newegg reviewers are intelligent, but 5+ PSUs exploding can't be user error.
 

Continuity28

Golden Member
Jul 2, 2005
1,653
0
76
Originally posted by: Sir Jman
read newegg reviews, sort from lowest to highest (I was looking at the 620). Now i know not all newegg reviewers are intelligent, but 5+ PSUs exploding can't be user error.

Like with every other piece of hardware, theres sometimes bad batches early on. I'm the proud owner of a Liberty, and I've built two other PCs so far that use them (400W and 620W). It's a fluke if true. I've never experienced quality problems with Enermax first hand.
 

Zepper

Elite Member
May 1, 2001
18,998
0
0
Or you can always get the new Fortron Epsilon 600 Watter - cool tech! Someone had it for $102. +sh per Froogle. See the review of its 700W big brother on http://www.xbitlabs.com pretty good job of analysis on the new design.

.bh.