Difference Bothers You? So Clone Old HD Instead!
As I said the differences under most circumstances is negligible. Althought there is a difference, the difference is relative to how often you access the files on this D:\ drive. But for the best long term solution and the ability to boot into the older drive, I would just clone the second drive as a partition on the first drive.
Best solution is to use a tool like ''Bootit''! Don't even need to install it, just put the install floppy in after a fresh start, and make sure you answer no to having ''Bootit'' choose the partition for you. Bootit will then go into maintenance mode. Of course this is presumming you already have the drive set as slave.
The 1st drive will now be showing for you to begin the install of bootit. But just don't install it, it will still make an easy job of it for you. You can begin by shrinking the partition on this drive to make room for the cloned partition from the 2nd drive. Make sure that when changing the size in ''Bootit'', you make enough room (either equal or greater) on the this first drive.
When the first partition is done resizing, you can just click your mouse on the 2nd drive in the left hand column. You see the 2nd drive now. Make sure the partition you want to copy is hi-lighted and click on ''Copy''. Go back to first drive (mouse click) and making sure the empty partition SPACE is hi-lighted. Now simply click ''Paste'' and you're about to clone that beastly old incompatible drive to your new Sata or any other drive type. Simply follow the instructions on this wonderful graphical tool and it will be done in no time. This is done all using "Bootit" on the 30 day full functioning trial.
If you want, you can even use this tool to boot any Operating Systems you have or would like to install, on any number of partitions. Even if you have more than four partitions per drive and up to, (I believe) 8 hard drives.
This tool is well worth the money and can even restore deleted or lost partitions, resize, re-partition, boot, clone, fix master boot record, and so on and so forth. I have had geat success with this tool over the last 7 years. Newest version is wonderful!