Looking for input on PSU choices

[ouberlord]

Hello all,

I am looking to upgrade my system by removing the x1900xtx and adding two Nvidia 9600GTs, but going by my low voltages I know that I am already skirting the lower edge of what I need to be at. My current PSU is some $50 piece of junk, rated for 450w. My current specs are as follows:

AMD Athlon X2 4800+ (2.40Ghz)
1x 80mm Aftermarket Cooler (Can't identify right now)
ASUS A8N-SLI Premium
2Gb DDR2 Memory (I don't know the speed off the top of my head)
ATI x1900xtx 512mb
SB Audigy 2 Platinum
3x IDE Hard Drives
2x Optical Drives
Various USB devices
1x 200mm fan
2x 120mm fan
1x 80mm fan

First up, what brand of power supplies are the ones to look at any more? Second, what caliber of PSU should I be looking for? Do I need some 600w monster for dual video cards and the rest of my hardware, or would a 450w that was purchased from a good brand do fine?

Edit: I have read through the stickied topic, btw. I just wanted some input from people as well.

 

[Dangman]

The problem with looking at PSU brands is that many PSU companies just buy and rebrand PSUs from other companies. Some of the rebranded PSUs are crappy while others are excellent. The best example of this is Ultra. Their X2 750W PSU is a POS but their X3 1000W PSU is an excellent PSU.

So basically, look at models, not brands.

Also, remember that wattage doesn't mean as much these days. What matters most is where those watts are being delivered. For current rigs, it's all about how much amps are on the +12V rail since most PC parts draw their power from there. The more amps you have, the more upgrades (hard drives, video cards, PCI cards, etc) you can add. You determine the amperage on the +12V rails by first finding out what's the total combined, max load, combined or max wattage aside for the +12V rails/section alone. Then divide that total by 12 and you get how much amps the PSU has on the +12V rail.

That's the correct way to find out how much amps a power supply has. Don't add up the amps on the +12V rail to figure out the amperage. Doesn't work that way. If the total combined or max wattage can't be found on the power suppply, check the manufacturer's page for that PSU for that info. If the manufacturer doesn't provide that information, it's generally a good sign for you to drop that power supply from consideration.

Read this FAQ on PSUs:
http://www.jonnyguru.com/forums/showthread.php?t=1036

But to recommend you a choice, the Corsair 450X 450W PSU should be enough to power that system:
Corsair 450VX 450W PSU - $76

 

[ouberlord]

That is an excellent explanation thread there, thank you. I took to reading through it and I now understand a lot more regarding the specifications of PSUs, but I have a couple more questions.

With that PSU you mentioned, I noticed it only has one PCI-e connection; should I opt up to the Corsair 520HX instead to get that second connector for the SLi setup?

Another thing I was wondering is that with modular power supplies with multiple rails such as that 520HX, is it set up so that each module port is set up on a specific rail? For instance, put the PCI-e cards on the third rail, the drives on the second, and the CPU on the first?

 

[Dangman]

That is an excellent explanation thread there, thank you. I took to reading through it and I now understand a lot more regarding the specifications of PSUs, but I have a couple more questions.

With that PSU you mentioned, I noticed it only has one PCI-e connection; should I opt up to the Corsair 520HX instead to get that second connector for the SLi setup?

Another thing I was wondering is that with modular power supplies with multiple rails such as that 520HX, is it set up so that each module port is set up on a specific rail? For instance, put the PCI-e cards on the third rail, the drives on the second, and the CPU on the first?

Actually the Corsair 520HX is a single rail PSU. The multiple rails was a misprint and by the time Corsair realized their mistake, a few thousands of PSUs were already produced with the misprinted label. Since changing the labels would require a huge chunk of change and time, it was decided to leave the labels as is.

However not 100% sure if each port on other modular PSUs is set up on a specific rail

As for SLI and 520HX, do you have a 24"+ monitor or game at 1920x1200 and above? If not, SLI is not worth it for you. If you do game at that resolution, then yes the 520HX is a good choice depending on what parts you choose.

 

[ouberlord]

I have a 22" widescreen monitor, but the highest resolution I normally go is 1680x1050. The reason I was thinking SLi though was that I was looking up benchmarks regarding the 8800GT card versus 2x9600GT cards, and though the pair of 9600GTs beat the 8800GT in more than a few tests and by a wide margin it was $40 cheaper overall. Of course, I haven't committed to this as an upgrade yet, but figured if I am to buy a new PSU anyway I may as well get one that would give me enough elbow room to optionally use SLi in the future.

So going by all of this would you still recommend that first PSU then?

 

[Manaknight]

i have the same resolution monitor, i can play nearly every game i have maxed out with my 8800gt on a bit of an overclock

that being said my fiance ran 2x7900gts 4 hard drives and an overclock core2 on the corsair 520 and it didn't so much as stutter.

personally i have the 620 corsair

see a pattern here? whichever one you go with get a corsair, i've seen them power stuff you wouldn't believe

 

[Dangman]

This quote best explains my position on SLI:

Just some info on SLI / Crossfire: It's absolutely not worth considering if a) you're gaming at a resolution under 1920x1200 (as you'll see no performance benefit over a single card,) and b) if you plan to buy one card now and another later. SLI / Crossfire as an upgrade path is usually a very poor idea, as by the time you're ready to get that second card, a new single card solution will likely be available that will outperform two of your older cards in tandem. Furthermore, there really is no cost benefit to the SLI Upgrade Route, as any additional cost in getting the new card can be easily mitigated in most situations by selling the original. By avoiding an SLI / Crossfire solution when it will not be of benefit, you gain a cooler running, simpler to maintain system and more importantly, access to a much better (and broader) selection of motherboards.

Also, I think you have your pricing wrong. The cheapest 9600GT I could find was for $165. Two of those cards is $330. A single 8800GT is $190. The difference between two 9600GT and a single 8800GT is not $40.

Or did you mean two 9600GT VS two 8800GT? Then the difference between the two SLI setup is $50.

Might as well go with the 520HX which will give you some headroom for any upgrade you might do in a year or two. Though for your current setup, the 450VX is enough.

 

[ouberlord]

Yeah sorry, I meant 2x 8800GT's versus 2x 9600GT's. So, a 520HX wouldn't be a bad purchase, sounds like that will be what I go with. Thanks for your help, you really cleared up a lot of confusion I was having.

 

[BF-2]

This quote best explains my position on SLI:



Also, I think you have your pricing wrong. The cheapest 9600GT I could find was for $165. Two of those cards is $330. A single 8800GT is $190. The difference between two 9600GT and a single 8800GT is not $40.

Or did you mean two 9600GT VS two 8800GT? Then the difference between the two SLI setup is $50.

Might as well go with the 520HX which will give you some headroom for any upgrade you might do in a year or two. Though for your current setup, the 450VX is enough.

Are you sure with 2 video cards you will not need more thatn 520HX?

 

[Dangman]

Are you sure with 2 video cards you will not need more thatn 520HX?

Depends on what other parts you have.