I recently added a second hard drive to my desktop. I have an 80GB Western Digital ATA-100 drive running my OS/Apps and I added a 400GB 16MB cache Seagate for data storage as the slave on the same IDE cable.
It appears the 80GB primary drive is running at UDMA-5 transfer mode but the 400GB Seagate drive won't run faster than UDMA-2.
The 80GB drive only has a 2MB cache so I would expect it to be slower than the 400GB with 16MB cache but am I missing something with the transfer rate? Shouldn't the 400GB be at UDMA-5?
I swapped out the 400GB and replaced it with an identical 80GB WD and they both ran at UDMA-5. Moreover, Windows identified the cable as an 80-pin, so I know the cable is not the problem. Any ideas on how I could optimize my drives?

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