it'll fit your motherboard.
Case; Measure from Back to start of HDD cage, if not long enough see if you can remove HDD bay sections, then it should fit.
There is nothing you need to know about the on-board chip.
You need a better PSU, Preferably; Seasonic/XFX/Antec/Corsair with at least 80+ Bronze certification and a minimum of 5 years warranty, 600W. If a PSU you found fits all those categories, then you know your looking at something quality.