PSU vs. GPU Question

ThisIsZachary

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Dec 1, 2009
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I'm considering buying a "customizable" desktop from HP (to the extent I can "customize" it).

I am interested in an ATI Radeon HD 4850 (1GB) card, and its website says it recommends at least a 400W PSU. The PSU HP wants to put in this case is only a 350W unit, but HP (sales) reassured me they wouldn't put incompatible GPUs and PSUs in the same configuration. Seems to me pretty black and white: the HP PSU can't give the GPU the power it needs. Is HP lying to me, or will the GPU work?
 
To really answer this we would have to know the Amperage on the 12V rails that PSU supplies. However, if it cannot supply enough power and they still put it in and you get it and it crashes, it is their problem, not yours since it will still be under warranty.
 

ThisIsZachary

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Dec 1, 2009
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Hi - Thanks for the quick reply. I Googled the PSU by mfr. and power rating, and I assume I found the right one (assuming may be wrong). But the specs say "+3.3V@15A,+5V@13A,+12V1@18A,+12V2@18A,-12V@0.8A, +5VSB@2.0A."

Sorry... not as PSU-literate as I thought. Also, as I'm moving out of the country soon, I'm not much interested in having to ship back a unit to HP for stupidity on their part! :) And I wouldn't put it past a salesperson to tell me anything I wanted to hear to make a sale.
 
That actually isn't too bad. The only info missing is what the combined 12V rail amperage is, but even without that I can guess. I have a mediocre PSU that easily handles a 110W CPU and 4850 and it only has about 18A on each of its two 12V "rails". So, that PSU may be acceptable.
 
Yeah, it isn't always listed. Another important factor is quality. I think Dell PSUs are pretty good, though I don't know much about HP. Some others around here know more about prebuilt PC PSUs, so hopefully they will see this post and respond.