Choosing the right CPU, GPU, or even SSD could be considered difficult - but so could simple peripherals, such as an HDD enclosure. These seem to be a dime a dozen, and while many consumer purchases may boil down to aesthetic value, we've discovered with Zalman's ZM-HE350 U3 that not all external enclosures perform alike.
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