Power Supply Size

TheUltimatum · Apr 30, 2009

After looking into new GFX cards, I realized I need to get a new PSU as well.

I'm looking into getting the Geforce 9800 GT for playing games such as COD 4. Currently I have a 300 Watt stock PSU which came with my HP a1730n.

I have been looking into power supplies such as Apevia and Diablo Tek.

My question is... Do I have to worry about the power supply size, and whether or not it could fit in my case? I am also looking for something over at least 450W, and has preferably over 26A on the 12+ rail.

McNinja · Apr 30, 2009

Apevia and Diablo tek make poor PSU's

please read in my signature about power supply selection

This is what you want to use for a 9800GT

Corsair 650w
$110
after rebate $90
http://www.newegg.com/Product/Product.aspx?Item=N82E16817139005

I would say $200 is your absolute minimum budget

Tumbleweed36 · Apr 30, 2009

Mcninjaguy has given you good advice on the PSU issue, the ones you have listed are basically junk. The one he listed is very high quality and at a very good price.

Phædrus241 · Apr 30, 2009

As long as the PSU you get has an ATX form factor and you have an ATX tower case, you shouldn't have to worry too much about it fitting in your case, though you may want to look at how your wires would be routed. When I installed my last PSU I had to move my DVD drive down to the expansion bay to make room for the wires.

TheUltimatum · Apr 30, 2009

Mcninjaguy, thank you for your help.

I am definitely going to consider those power supplies that you had in your post.

I'm not sure if I have an ATX case, is there a way to check on manufactured PC's?

Also, I was looking into this power supply, is it perhaps a good one?

http://www.tigerdirect.com/applicat...?EdpNo=3287208&csid=ITD&body=MAIN#detailspecs

Wrench97 · Apr 30, 2009

It is a good one but not large enough to run a 9800GT, the minimum power requirement your seeing is just plain incorrect Video card Manufacturers low ball the number in order to sell more video cards, then when you have issues 6 months down the road and and call tech support will tell you it's power related.

Forgot the A1730N does take a standard ATX12v size PSU.

McNinja · May 1, 2009

@TheUltimatum

That PSU isn't powerful enough

TheUltimatum · May 2, 2009

Accidental spam.

TheUltimatum · May 2, 2009

Mcninjaguy said:
@TheUltimatum

That PSU isn't powerful enough

9800 GT's run off 400 Watt PSU's. Running 2 9800 GT's SLI is 450 Watts.

Tumbleweed36 · May 2, 2009

TheUltimatum said:
9800 GT's run off 400 Watt PSU's. Running 2 9800 GT's SLI is 450 Watts.

I don't know where you are getting your information from, but this is not accurate at all.

You need 600w bare minimum to run one 9800gt, 650 to 700w or higher is best for a single card and for sli, try a quality 750. If you don't get a supply that has enough power, you will regret it.

oldjoe · May 2, 2009

Minimum PSU is 400W with +12 Volt current rating of 26 Amp for a 9800GT.
That is according to Nvidia. http://www.nvidia.com/object/product_geforce_9800gt_us.html

Tumbleweed36 · May 2, 2009

I don't disagree what the advertisement says, but the companies underestimate those needs to sell more video cards with lessor power supplies. Those are the BARE minimum and are not powerful enough to do the job that needs to be done with these high powered video cards.

Here is some information that we on the Hardware Team have found very helpful from some indept research on that issue:

http://www.techsupportforum.com/f238/video-card-quick-list-371158.html

oldjoe · May 2, 2009

A 9800GT draws a little over 200W....a 9800GTSLI draws around 230W.
Both draw about 19 to 20A.
Power requirements (calculated using eXtreme PSU Calculartor)using a High End MOBO-Quad Core 9650CPU-4 sticks of DDR2 RAM-9800GT Graphics Card-2 7200RPM HDD's-2 DVDRW's-and 4 1200MM Fans comes to 327W.

Tumbleweed36 · May 2, 2009

Well oldjoe, we will just have to disagree on the needs for these video cards. I think you will find almost every tech on the hardware team will also strongly disagree with your assessment. You are entitiled to your opinion, but the raw figures don't take everything in the rig into account.

I stand by my original estimate of what is needed for the OP. If you want to know more about power supplies, then take a read of this power supply document that was created by using several distinguised members of the Hardware Team:

http://www.techsupportforum.com/f210/

Please note: UncleMacro who authored the "Playtool" series on video cards and is considered by many to be an expert in this area, was a member of this power supply team. He provided valuable information that was incorported in this document. I don't think either you or I can match his expertise in the power supply/video card area. Our resident team member expert emosun has also written a sticky that I noted for you to read in the area of video cards and his assessment also disagrees with your assumption of the power needs.

http://www.techsupportforum.com/f238/video-card-quick-list-371158.html

I will leave it at that and say we will never agree on this one. Have a nice day.

Wrench97 · May 2, 2009

How about from XFX's web site you'll notice the minimum is listed as 600w for a 9600GT.
http://www.xfxforce.com/en-gb/products/graphiccards/9series/9600GT.aspx#4
A lot has to do with the quality and rating system used to determine the wattage on the sticker, some are peak ratings, others are peak ratings at 25c a temp the power supply will never see once turned on.

McNinja · May 2, 2009

Whatever PSU we recommend we take into effect that we want it o last a long time for the OP. We are just volunteers and as that out of the best interest for your wallet and the quality of your computer we want to to make sure you'll have a computer that won't fail early on.

You might be able to run the minimum PSU for about 3 months and then you'll notice lag, weird errors, heat issues (from incorrect voltages), nobody wants those things and the PSU is the heart of any computer. Without a clean power supply and computer can't function properly.

oldjoe · May 2, 2009

Tumbleweed36 said:
Well oldjoe, we will just have to disagree on the needs for these video cards. I think you will find almost every tech on the hardware team will also strongly disagree with your assessment. You are entitiled to your opinion, but the raw figures don't take everything in the rig into account.

Disagreement is what makes the world work.:grin:
However, my post is not based on my opinion.....it is fact as the included figures show.
The calculated list I provided includes "everything" and maybe some extra for a quality PC. Personally, I would certainly include more power than the required 327W but that list validates my post. The 9800GT can/will perform with no problems with a quality 400W PSU.

wrench97 said:
How about from XFX's web site you'll notice the minimum is listed as 600w for a 9600GT.
http://www.xfxforce.com/en-gb/products/graphiccards/9series/9600GT.aspx#4
A lot has to do with the quality and rating system used to determine the wattage on the sticker, some are peak ratings, others are peak ratings at 25c a temp the power supply will never see once turned on.

Given the quality of XFX, at least my experiences with them,I wouldn't be surprised if they required even more power than they list. :grin:

McNinja · May 2, 2009

when you use a PSU calculator you need to take two things into effect

30% capacitor aging
ADD 50% for long usage of a computer

your argument is invalid oldjoe, we recommend PSU for long term usage.

oldjoe · May 2, 2009

Not an argument....only facts that haven't been proven incorrect. I'll let it lie.
In the future, please show me the courtesy of spelling my username correctly.

McNinja · May 3, 2009

I'm sorry I thought I fixed my grammer. I should've double checked my post.

If you don't believe the experts than, there's not much I can say with all the facts in the power supply selection sticky in my signature.

Power Supply Size

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