Hard drive compatibility for x21?

[wondercow2]

Is there any reason that anyone can think of as to why IBM would list a newer, 40-60 GB, 5400 RPM, ATA 5, 9.5mm drive as incompatible with a system that originally came with a 20 GB, 4200 RPM, ATA 5, 9.5mm drive?

The old Hitachi drive in my new-to-me X21 is making unhappy noises as the machine accesses the HD every second or so. It doesn't sound like full-on failure and the important SMART readings are within spec, but SMART does indicate that the drive has exceeded its "Load cycle count", which tells me the poor guy was probably sitting turned on 24/7 on someone's desk in its previous corporate life.

So I want to replace it with something new, and preferably quieter and more shock-proof, but I don't want to end up with an incompatible doorstop either. I was under the impression that until SATA came around all ATA hard drives were backwards-compatible, so why would IBM claim that a slightly newer style of drive won't work as a primary system drive? Are there thinkpad-specific problems that will prevent a newer drive from politely slowing down to the maximum performance limits of the motherboard components? I'm running Win2k, so I can't imagine that disk size alone is an issue.

[dmdsoftware]

I have no problem running a 40GB 5400rpm HD on any of my X2*s.

[Kurt]

60GB HDD will work fine with X21. But I'm not sure about more than 80GB.

When the X20-21 was originally introduced, no high-capacity (mroe than 40GB) 2.5 inch HDD were developed. That's the reason why IBM has no specifiec limit on compatible HDD.

Dell, HP, and Sony are the same case about the HDD capacity matter at the time.

Classic ThinkPads such as 570E, 600X, 770Z can accomodate up to 60GB. (in some case, after updating BIOS) But the user's manuals have no information about that, because there were no 40 or 60GB HDD when those laptops were introduced to the market.

[whizkid]

All of these machines (anything that will handle over 8GB) should handle up to 138GB with no problem.