I put a Western Digital Caviar drive into my Performa 5200 (same case design as the 5400), and it works great. The Western Digital drives are usually a bit more expensive, although some people swear by them (not me). If you live near a Fry's electronics, you can get a good quality (Fujitsu, Quantum, Maxtor, IBM) 10 to 13GB drive for about $120-130 (I was at Fry's tonight, and I remember looking at the prices). HD's on the net run for around the same prices. Check pricewatch.com for the lowest price.