as a follow-up...i installed the new 7200.10 sata2 drive and ran HDTach. when comparing it to the 160GB sata2 drive that came with the dell pc (also a seagate, but a 7200.9 w/ 8mb cache) i found that the older 160GB drive was performing much faster. hmmm. burst rate was much better on the older drive w/out the perpendicular recording technology. strange, eh?
well, i poked around trying to find how to tell what speed sata drives are operating at (not as obvious as looking at the IDE controller modes for DMA5, etc). finally found it in the BIOS listed as "drive link speed". the new drive was only linking at 1.5Gb/s and the primary drive was 3.0Gb/s. hmmm again. what's up with that?
sooooo, i think maybe i am dumb and there is a difference in sata vs sata2 cables...nope...google tells me otherwise.
luckily (can't believe i found this) i find an article on Seagate's website:
http://www.seagate.com/support/disc/sat ... 812as.html
a jumper came FROM THE FACTORY set to 1.5Gb/s...basically crippling the sata2 drive out of the box. WTF.
so, i remove the jumper (which sets it to "normal" mode) and it links up at 3.0Gb/s w/out issue.
HDTach before: burst = 128.8MB/s
HDTach after: burst = 234.9MB/s
(older 7200.9 160gb drive = 205.6MB/s)