You have nearly same model as mine.
http://www.pcworld.com/reviews/product/379631/review/aspire_ax1301b1812.html
First of all, to do this would be almost like re-building your whole PC. You will need a new case to fit a relevant power supply. Slimline desktops are not very upgrade friendly. I would imagine you need the new supply to power a graphics card you are trying to install? Same issue here. 220 watt is terribly small. Try this site for good info on building pc from ground up. You do not need all the info there, but enough of it will apply to what you need to do>>http://www.mysuperpc.com/
Don't mind the sites cartoony look, it still has good info
I for one will never buy slimline again for this reason.
I have an Acer Aspire X1800-E1232 - P E5400 2.7 GHz, and I want to upgrade my power supply but I have no idea what kind of power supply to get model wise. Are power supplies 1 size fits all?
Thanks in advance!
http://www.zdnet.com/reviews/product/desktops/acer-aspire-x1800-e1232-p-e5400-27-ghz/34357699

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