qwoz :
idk what people don't understand about small form factor pcs. no psu that is worth buying is going to fit. i would need a micro atx witch is no better. why i put one on the outside when i could fit one inside???
Well for one you need to run across someone who has actually mounted a P/S on the outside of a case, and you just did!
I have an OP1000w Silverstone mounted on the side of my case, with my wiring harness brought through at an appropriate point to reach all the necessary connection points, that required cutting an access hole in the side of my case, and my reason was the OP1000w is 8 5/8" long, 3" longer than a standard ATX P/S, seriously blocking my 140mm blowholes I had previously modded into the top of the case.
The problem with a Dell, HP, Etc. is they make their cases so small the smaller P/S is all that usually will fit, and normally they only provide enough power to cover what comes in the computer when you buy it, so when you upgrade most people have to send their machines back to get it upgraded by them, costing you more money than it should.
I congratulate you on thinking outside the box, most quality ATX P/Ss have longer cables than the smaller P/Ss do anyway, you can research different P/S specs and get the exact cable lengths, and if you find some long enough you can just route them through the existing P/S opening, that won't look too good but will solve your problem.
Even altering an existing case to accept a full size ATX is possible with some computer cases, I altered a HP Pavilion just for the heck of it and installed a full size ATX 700w Fortron P/S, so anything is possible if you put your mind to it!
I'll be glad to help you through this information wise, as much as you want! Ryan