I have found Western Digital drives to be pretty flawless in performance and durability. The "Raptor" weighs about twice as much as a regular IDE drive. It is a very high quality drive made of high quality materials. In fact, the "Raptor" comes with a 5 year warranty! True, as a previous poster mentioned most trading applications don't require heavy "reading and writing". I am currently using the "Raptor" as a second drive for many of my download applications. It is wickedly FAST! While the "Raptor" might not be for everyone I would certainly suggest getting a Serial ATA Drive with an 8mb buffer. If you don't feel comfortable with the slightly higher noise level that comes with a 10,000 RPM drive, try the 7200 RPM Serial ATA drives. Serial ATA is the next Big Thing! The much smaller cable that supports Serial ATA vs the conventional "ribbon" drive cable will aid in cooling the inside of your computer and as I said earlier, most of the "newer" motherboards support Serial ATA and thus does not require the need for a controller card. The data-transfer rates are HUGE, and will get even bigger in a couple of years. The top of the drive runs warm to touch and the bottom of the drive runs a bit hotter. I also installed a Vantec Hard Drive Cooler for $10.95 that comes with 2 x 60mm ball-bearing fans for a bit of airflow over the drive, just in case. If you don't believe me, check out a very meticulous "test" in the following weblink from TOM'S HARDWARE GUIDE: http://www6.tomshardware.com/storage/20030501/index.html
Installed the maxtor 40GB HD that Vhehn suggested and is working flawlessly. Some notes: I originally loaded it with the win98 CD and had problems with the display and other devices. Even went as far as downloading some drivers from the compaq website. No help. Compatibility issues maybe? Waggie's on it. After some hours I gave up and tried the system restore CD. It took a while to load everything but no problems whatsoever. Just remember to have your chassis serial number handy in case the restore disks ask for it (mine did) otherwise it won't let you in. Thanks again for the assistance everyone.