Yes you can. wether your BIOS recognizes the entire thing isn't really relevant.
I read in several places (including Microsoft's site) that if you use a HDD larger than 137gb on a system that doesn't support 48-bit addressing you would lose data and Windows would eventually become corrupted. But I think that's referring to both the BIOS _and_ Windows XP. If that's the case, since I have SP1 (with 48-bit addressing) it isn't an issue.
After all this, I'm starting to realize (more than I already did) that 99% of people on message boards don't know what they're talking about. I've been told a million different things with no backup whatsoever.
Logically I assume if Windows can't access anything past 137gb on the drive (by installing it on a smaller partition) it can't put any important information in a space where the BIOS can't get to it, which means BIOS will never have a problem loading Windows. And if, while using Windows, the partition gets full, it would just say "Hey this disk is full", it won't automatically wrap around to the beginning and start overwriting files there like people say it will if you don't have 48-bit addressing and don't partition the hard drive to smaller size, or start writing to another partition on the drive and overwrite files there.
Wether yo uget a new 80GB or a 500GB, it's going to be better then what you already have because the drive you have is failing. If you don't get your data off of it, it's gone.
All my data is already backed up (most twice, some of it three times).
The point is; what if it dies while your agonizing over the details of your new drive and presenting theories on you BIOS limitations? Then it won't really matter much, will it.
What if I just went and did it, and messed it up worse because I didn't know what I was doing?
Installing a drive isn't going to fry your computer except in the very rarest of circumstances, and if you're going to worry about that, you better start worrying about getting hit by lightning on a clear sunny day, or that one day you'll walk outside your house and be attacked by a naked midget with a bazooka. Same chances.
LOL
Lastly: you've only referred to the motherboard as "motherboard from 2001" and other rather vague indications. Can you give the entire model number so <we> can actually research for the relevant information too? (that is, wether it can work with 48-bit addressing,BIOS update availability, etc)
It's Chaintech Apogee 7VJL. if you can find any info that would be great, but I and other people have looked and not found any. As I said, Chaintech doesn't do motherboards anymore, doesn't have any info for them on their site, and doesn't respond to messages about them. Archive.org has some of the drivers that were available on the site before they removed that section, but there' no way I'm going install new drivers haphazardly just to see what they do.
In any event, I did buy the 500gb drive on Sunday, installed it yesterday (well, plugged the cables from the old drive into the new drive and left the new one sitting on the bottom of the computer enclosure so I can switch back if I need to) and clean installed Windows XP on a 120gb partition. (The cloning process failed because of sector read errors so I gave up on it.) Not surprisingly, the motherboard only sees 136gb of the new drive, but Windows does load fine. Started installing some hardware (sound card is working) but now I can't get the network connections working. I will have to post a new message to see if anyone has input on that.
In the meantime I've switched back to the old drive so I can try to get some help. I'm posting this message from the old drive, so thankfully it was correct that you can just plug the old drive back in and go back to what you have before.
BTW I do understand what you're saying about overthinking the process, but I'm not some computer tech guy who's familiar with these things. I've never even installed Windows myself before, let alone installing a new hard drive--I didn't know anything about formatting and partitioning--and before I could do it I needed to find out as much information as possible so make sure I didn't do something wrong. I didn't know anything about any of this it until a few days ago. It's a lot of information to absorb in a short time and I needed second opinions.