Help with buying PSU

dan_plus_o

New Member
Hello, I am going to be building a computer soon and I have chosen all of the main computer components but now I have to pick a PSU for it all.

Here is what I am going to have:
Motherboard: eVGA nForce 680i SE SLI (TR Version)
Processor: Intel Core 2 Duo E6850 (3.0 GHz)
GFX: eVGA e-GeForce 8800 GTS Superclocked 320MB PCI-Express
Ram: 2GB OCZ DDR2 OCZ2N800SR2GK PC2-6400 SLI-Ready Dual Channel
HDD: Western Digital Caviar SE16 500GB SATA
OS: Windows XP Pro

For the Hard Drives I will eventually want to have 3 Hard Drives. One for the OS, another for Normal use/gaming, and another HDD for my audio recording projects. I will probably get a 10GB, and two 500GB.

I know the Geforce 8800 GTS needs a minimum 400 watt PSU with a +12 Volt current rating of 26 Amps.

I might want to run two Geforce 8800 together in the future and according to this post:
http://www.computerforum.com/90110-power-recommendations-video-card.html
I need a 650Watt power supply with 52 Amps to do that.

Now I am am pretty sure everything I have already picked above will all work together (If not please tell me) but for the PSU I am really not sure what I should get.

I am going to be buying all my stuff from Anitec.ca so if anyone could recommend a PSU from that online store that would be great.

By the way, anyone have any experience with Anitec.ca? They seem to have really good prices but are they a good place to deal with?

Is this a good PSU to get?
http://www.anitec.ca/product/9411/cooler_master_extreme_power_650w_power_supply/
I would definately like to get a cheaper one so I have more money for a LCD monitor, but I don't want to end up with a bad PSU.

Or maybe this one:
http://www.anitec.ca/product/8822/ocz_stealthxstream_600w_power_supply/
 
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The Coolermaster is OK for a single 8800GTS, but won't be able to handle two. It's actually a rebadged Seventeam 500W PSU, which is rated for +12V@30A.

The OCZ StealthXStream is better, and would certainly be better than the Coolermaster, but still isn't something I'd recommend for SLI'd 8800GTSs. It's very much the bare minimum in terms of output power, and the high ripple would be a concern at those sorts of loads.

Anitec have an Antec TPIII 650W for $115.95, and a Corsair HX620 for $125.95 after rebate, which are better, albeit more expensive choices. They'd be about the smallest I'd be willing to recommend for SLI'd 8800GTSs.
 
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Okay thanks for the info.

So just to make sure.. Is this the one you are talking about?
http://www.anitec.ca/product/6743/antec_truepower_trio_650w_power_supply/


I won't be running two 8800 anytime soon but I would rather get a PSU that I won't have to upgrade later down the road. Is it okay to have a big 650W PSU when I am only using one 8800?

or how is this one?
http://www.anitec.ca/product/9519/antec_neopower_650_blue_650w_power_supply/

or this one?
http://www.anitec.ca/product/6237/ocz_gamexstream_700w_power_supply/

The Corsair HX is only 620watts so would that work with two 8800's because I read a sticked post here that said two 8800 need a 650watt PSU with 52 amps.
 
The corsair 620w puts out 50a, the OCZ 700w puts out 50a. Of those you have listed above i would get the gamexstream. But for quality i would get either the Corsair or the OCZ GameXStream model.
 
So will 2 amps make a difference? Because I read that for two 8800 you need a PSU with 52 amps.

I want to get a PSU that will work with SLI (two 8800) so if I decide to get another 8800 down the road, I won't have to upgrade my PSU.

Is there a down side to getting a 700 watt PSU if I don't need it right away? Will a 700 watt PSU make the hydro bill go up even if I am not needing all of that 700 watts? Or will the computer only take as much power as it needs?
 
Okay thanks for the info.

So just to make sure.. Is this the one you are talking about?
http://www.anitec.ca/product/6743/antec_truepower_trio_650w_power_supply/

or how is this one?
http://www.anitec.ca/product/9519/antec_neopower_650_blue_650w_power_supply/
It was the first one I was referring to, but either will be fine.

The GameXStream has the same problem as the StealthXStream with regards to ripple that exceeds ATX specifications at high loads. Aside from that, they're not bad units, but when the Corsair is in the same ballpark price wise, I'd be buying the Corsair - they're not really in the same league quality wise.

I read a sticked post here that said two 8800 need a 650watt PSU with 52 amps.
I know, I remember writing it :D. In truth, those are general recommendations. Two PSUs with identical ratings are sometimes capable of putting out vastly different amounts of power, so I have to be a little conservative when stating general recommendations. The Corsair is conservatively rated for 620W continuous @ 50C, which is a lot more than I can say for some PSUs. It will work for a system like yours, Corsair have proven that.

Is there a down side to getting a 700 watt PSU if I don't need it right away? Will a 700 watt PSU make the hydro bill go up even if I am not needing all of that 700 watts? Or will the computer only take as much power as it needs?
No there's no downside - a PSU will only draw as much power as it needs
 
I just noticed something about the Corsair 620HX PSU. The fan is located on the bottom of the PSU and I am getting a Antec 900 case that has the PSU mounted on the bottom of the case.

So would I have to install the PSU upside down? And if so, is is alright to have a PSU upside down?
 
I just noticed something about the Corsair 620HX PSU. The fan is located on the bottom of the PSU and I am getting a Antec 900 case that has the PSU mounted on the bottom of the case.

So would I have to install the PSU upside down? And if so, is is alright to have a PSU upside down?

Same concern was here when I bought the Antec P180, I slapped myself on the forehead when I noticed there was space for the fan to blow under that raised platform.
 
Okay, so I got my Antec 900 case and the Corsair CMPSU-620HX PSU. There is no gap for air to flow under to PSU. So I pretty much have to mount the PSU upside down. Is there going to be any problems if I mount my PSU upside down?

I just found this posted on another forum.
i once had to mount my PSU upside down, and what happened, was that the heat would rise back into it and it got real hot, and it made my computer unstable etc, so didn't work out for me

That would suck...

Then I found this:

Looking into the Corsair HX series, it appears this may be a preferred mounting form as the circuit board and components will be oriented upwards. As heat rises, this should reduce circuit board heating as heat will rise and theoretically be collected by fan airflow to outside the case/back.

So that sounds good..
 
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Antec, I know, actually drills their holes in such a way that a PSU could be mounted either way, so mounting shouldn't be a problem. As mentioned earlier by people far wiser than I, the only thing you'd have to worry about is whether upending all those internals is going to cook some critical part. And really, that's hit-or-miss with different PSUs. Have you checked the manufacturer's website for a support forum? There might be a thread on there about "alternative" mounting options, including the heat-soak issue.

As a random suggestion, if you can't return the PSU and don't have the money to invest in another quality unit, you could simply mount the PSU externally (in a well-ventilated area, of course) and run the wiring through the case's mounting hole and the 900's rubber watercooler tubing grommets. This would be ugly, but it would work.
 
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So the other day I wanted to see what my antec 900 case looked like with all the led fans so I installed my Crosair 620HX PSU and then plugged all the fans into it. I turned the switch on the PSU and nothing happened.

Is that normal? I only plugged the fans into the PC so does it need to be plugged into a motherboard before the PSU will turn on or should it of turned on with just fans plugged into it?

A quick google search cleared that up:
http://forums.tweaktown.com/showthread.php?t=18420

EDIT:

MMMM.... The Antec 900 looks so nice with its blue led fans... But it is sure to annoy me when trying to sleep... I could probably rig up some kinda switch to turn the leds off. I did that with my xbox console so I can turn all the leds off with a flick of a switch.
 
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You need to have the PSU plugged into the mobo before it will do anything. The GFX connector too. Plug in EVERYTHING.
 
Thanks for posting oscaryu1... although I ended up getting the PSU to turn on by bridging pin 14 (Green-power on) with pin 15 (Black-ground) of the main motherboard power connector.
 
Okay, so I got my Antec 900 case and the Corsair CMPSU-620HX PSU. There is no gap for air to flow under to PSU. So I pretty much have to mount the PSU upside down. Is there going to be any problems if I mount my PSU upside down?

I just found this posted on another forum.


That would suck...

Then I found this:



So that sounds good..

nono.

my friend has an antec 900 and a fortron 500w, it fits fine, the case is built such that the psu is supposed to mount upside down, with the fan sucking cool air from the bottom of the case
 
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