I'd run a the Diagnostic Software (SeaTools) Seagate-exclusive hard drive diagnostic software designed to troubleshoot most hard drive issues. To me it sounds like a bad sector on the HD. You know what that clicking is. I'd be saying why me!, but the same problem on multiple new HD's, I'd be scratching my head. BTW - beautiful system you built there. Here is a link that might be useful: SeaTools

There was a size limit with early versions of XP, which is what you're probably running into if you using the original install disc. How are you installing Vista? If from a disc, just point Vista to the drive as part of the install and it will format it for you. Otherwise, assuming you're running XP with Service Pack 3, just format it from inside of Windows.

fwiw Speaking of backups... recently playing around... Have 8gb ram so I used a freeware, RamDisk, a very small program, to make a RamDrive = 770mb for RediBoost & balance for Browser cache & windows low disk space avoidance. Anyhow while searching web for how people use ram disks trying to figure out what I was doing wrong .. initially my startup & shutdown times went up ... I came across a regedit setting on increasing hard disk cache.. for win 7 / vista anyhow.. maybe same for xp. HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management LargeSystemCache default 0, changed to 1 = supposed to be hard drive cache. ......... after changes both graphics ratings went up .1 from 6.2 to 6.3 in Windows Experience Index Daily backup & image went from 17 minutes to 11 consistently . Just confirmed once now, it was the registry change that sped up the backups. Thats quite a time savings here ... I usually stop and twiddle my thumbs when backup runs. Thought some here may be interested in trying that registry tweak.

More memory is good but at some point there is a diminishing return on the investment and that point is a function of what you are doing with your computer. Things like first person shooter games, video editing, photo editing (of very large files) all benefit from lots of memory. Writing an email to Aunt Betty doesn't require very much memory at all because the computer can process information far faster than you can type. Same thing for the Internet, your computer can render pages faster than your connection can supply the information. So if you have a slow internet connection, you're not likely to experience much, if any improvement. With that said, 4 gigs is probably a pretty good number. If you really want a WOW factor, get a solid state drive and use that for your O/S and critical applications. To try and answer some of your questions: - Windows doesn't care about the physical drive or any logical partitions. It does make good sense to install Windows 7 on the newer, faster drive. You'll get the best performance that way. When it comes time to get rid of XP, everything will be on one drive and that, if nothing else, should help you keep things mentally organized. - My understanding is that you have two physical drives, one with a functioning version of XP and the other blank. If that is not correct, say so NOW. - When you go to install Windows 7, it will recognize that there is another operating system (Windows XP) already installed. Windows 7 won't do anything to XP other than to set up the dual boot. Essentially it's computer language that says, "XP is there, Windows 7 is here, which one do you want to use?" - Logical partitions to a drive a largely a function of personal preference. Understand that it is more difficult (but not impossible) to non-destructively repartition a drive after you put data on it. If you, for example, have a partition for music, another for videos, and a third for pictures and find down the road that you have a lot more videos than music, it becomes more difficult to rearrange things. My suggestion is a single, large partition and use folders to organize your data.