Re: help here
Just buy a new one which has a voltage rating of about 350 watts for that machine, though I'd get one with 400 watts for if you changed PC's soon.
Also, quality on PSU's is important, though you should be able to get one for $25 I' think, though a good one to protect your system if anything went wrong?...I don't know. Post some makes you see on websites, etc and i'm sure people will tell you if there good or not.
The people in the shop might have been trying to flog you a 600 watt or 500 watt which you wouldn't need with that system.
I hope this helps
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