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Old January 7, 2010, 11:09 AM
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bojangles bojangles is offline
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My System Specs


Originally Posted by CMetaphor View Post
Good point. But then again... unless im just too tired to understand phyics today. Wouldnt a single platter 3.5'' hard drive's outer edge spin faster at its outer edge running at 7200rpm than a 2.5''s outer edge running at 10k rpm? Perhaps my "lil fast and easy brain math" is off today.

the 300gb aerial density doesn't win it for the vraptor actually... dammit, math time:
Area of a 2.5'' disk would be Pi x 2.5''/2 = 3.92 inches cubed (not including the unuseable space in the very center)
Area of a 3.5'' disk would be = 5.497 inches cubed.

If the aerial density of the 2.5 is 300gb, then its managing approximately 76.53 gigs per cubic inch.
For the 3.5 @ 500gb aerial denisty, it would be 90.95 gigs per cubic inch

therefore, the 3.5'' disk with 500gb aerial density still has a marked advantage. I wonder if the faster RPM of the vraptor will make up for it?

PS: anyone can correct me on my math if im wrong - i dont like math. lol
You got it all wrong lol.

Area of 2.5" disk would be Pi*(2.5/2)^2 = 4.91 inch sq.
Area of 3.5" disk would be Pi*(3.5/2)^2 = 9.62 inch sq.

Areal density of 2.5" disk = 300/4.91 = 61GB/sq in.
Areal density of 3.5" disk = 500/9.62 = 52GB/sq in.

So the 2.5" platters are more dense.
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