# Upgrading PSU on HP Elite Desk 800



## JSmitth

Hi there,

I have an HP Elite Desk 800 G1 Tower that I would like to upgrade the 320W PSU in, to accomadte a GPU.

The problem I found is that the stock PSU has an odd cable that I have never seen on a PSU before, and I don't know which PSU I would need to buy to make sure the system still works.

This is an image of all the cables coming out of the stock PSU. It is connection P2 that I am unsure of. It connects to a motherboard header labelled 'pwrcmd' as shown here.

Other specs:
Mobo: HP18E4 Q87 Chipset (According to HWINFO) couldn't find another name on the board, only this sticker.
PSU: HP Part No 702453-001 (Rated at 320W, 12VDC output, 90% efficient (EPA90)) Label.

Thanks for taking the time to read this, I really appreciate any help!

JSmitth
http://i.imgur.com/zzkO4JD.jpg


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## DBCooper

Hi JSmitth,

May I ask, what brand/model of GPU did you buy? Or, you haven't bought it yet?


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## JSmitth

Hi DB,

Not bought yet, but looking at most likely a GTX970, as I need a reasonable amount of GPU power. I did look at a 750ti to run off of the motherboard, but it's just not enough power


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## Panther063

I would recommend looking through the build guides and building a new system that is suitable.
H.P. use proprietary PSU's and Motherboards making upgrades near impossible.


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## alpenadiver

i agree with Panther063, the big name computer vendors use a proprietary PSU, even if you did find a off the shelf PSU that had the correct connections (which is highly doubtful) the next obstacle would be fitting the PSU in the computer.

This is why home built systems are much easier to upgrade.


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## Bill_Bright

I agree with building a new system for the same reasons given, but that's a MUCH bigger endeavor (not to mention MUCH more expensive). 

I am shocked - in a very good way - to see the 80 PLUS Gold logo on the image of that PSU. It takes an excellent design using quality parts and refined assembly techniques just to get *80 PLUS* certified. To achieve a Gold rating is even more remarkable - for any supply, let along an OEM.

So I have to say I am seeing HP in a different light and have a much better respect for them now - at least when it comes to power supplies.

My concern is when looking at the computer's specs I don't see ATX anywhere.  Since this computer is pretty new from last year, I want to assume this is just a slimline ATX supply. My problem is, I would hate to assume that, then hear you fried your motherboard with a real ATX compliant PSU. 

If me, I would connect a *PSU Tester* to your current supply. If no errors (except the normal -12VDC missing error), then I would feel comfortable saying you can replace that PSU without going through HP (which would be more expensive, if any are even available). 

The advantage of this model PSU tester is that it has an LCD readout of the voltage. Lesser models use LEDs to indicate the voltage is just within some "range". These are less informative, considerably cheaper, but still useful for detecting PSUs that have already "failed" - or in your case, to verify your PSU is wired to ATX standards. *Newegg* has several testers to choose from.

Having said all that, how much RAM do you have? If looking to boost performance, depending on your starting point, adding RAM generally provides the most bang for your money - especially if using integrated graphics. And the advantage of adding RAM vs a new graphics card is you most likely won't need a bigger PSU.


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