I have found many 550w 80+bronze psu's but i donk know if they can fit in a lenovo thinkcentre M90p, imm looking for the 30-45 dollar price range, I also can save up for a cheap case in case no power supplies fit. Thanks,
wtleger80
Looking at the inside of that case (Based on a google search) I don't think you can fit ANY aftermarket PSU into there (assuming its not the "tower" version I have also seen). Also that motherboard is a BTX which means you need to find a BTX case which is fairly rare. BTX basically has the ports and the slots swapped so the slots are on top.
Now a recommendation for a PSU would be the XFX TS 550w
The smallest one has actually an external AC-DC power brick.
Exactly, its basically non upgrade-able, it can't fit a full graphics card, you can't swap cases. Maybe can add some ram or change the processor thats about it. Unless you really want to frankenstein it.