The Seasonic G Series PSU is here for review in its 550 watt capacity and it looks to be a return to basics for the company with this being basically a "no-frills" unit that has been released without much fanfare. But the basics for Seasonic usually outline what you truly need in a PSU; reliable clean power with a low sound profile.
Slow computer got you down? Maybe a hardware upgrade should be in your cards, if so this guide to the Fundamentals of Upgrading a PC is an invaluable read. PCSTATS Tips