The hard drive is one of the most common computer upgrades consumers perform, and it is no secret to some that the more gigabytes you buy the less expensive (per gigabyte) the drive is. I have compiled a list of the most common drives in each size category, and created a cost-per-gigabyte comparison chart. I have shopped NewEgg.com for these prices, and have given a link to each drive. I generally chose the least expensive of each size category and have also listed the cache size next to the model. The higher the Ratio the better, as it indicates how many gigabytes each of your dollars is purchasing. Also, one last thing to keep in mind: Most of the drives have free shipping, but if they do not it will decrease the ratio.

Drive	Size	Cost	Ratio
Western Digital Caviar SE 8MB	80GB	$34.99	2.29
Western Digital Caviar SE 8MB	160GB	$41.99	3.81
Western Digital Caviar SE 8MB	250GB	$49.99	5.00
Western Digital Caviar SE 8MB	320GB	$49.99	6.40
HITACHI Deskstar 16MB	500GB	$59.99	8.33
Western Digital Caviar 16MB	640GB	$69.99	9.14
Seagate Barracuda 32MB	750GB	$79.99	9.38
SAMSUNG Spinpoint 32MB	1000GB	$99.99	10.00
Seagate Barracuda 32MB	1500GB	$129.99	11.54

I remember it wasn't less than a year ago and the best drives had a ratio of around 6-7. Hard drive sizes are increasing exponentially and prices are falling at the same time. Any of the drives over 500GB are a great buy, but if you want the best bang for you buck, the 1.5TB (1500GB) Seagate drive is the hands down winner.

Series	Hard Drive Cost Charts
Tags	newegg   hard drive