Why wont my harddrive boot? Urgent

This is a sequel to my other post, but its a little different now. I've found some new things out.

First off, I installed XP Pro onto my old 2.1gig drive I had lying around (dma 50 5400rpm or something ) and I'm actually online with my computer now. The problem is, the boot hdd still wont boot. When it comes time to loading windows it gives a blank screen and then text shows up saying:

Disk Read Error
Press ctrl+alt+del to restart

Ive done everything I can think of, chkdsk checking bad sectors (which it said it found one or more errors and repaired them, but nothing) writing new boot sector. The only thing I havent tried is resizing the clusters back down, maybe for some reason xp wont boot with 64k clusters.

I remember when I had my pata drive as boot partition magic wouldnt let me resize larger than 4k clusters. This time the 64k went through and it wont boot. Could that be related? They were originally 512 byte clusters.

I can get into the drive from this install of windows, I've already backed up all the important stuff on there. I just dont want to have to reinstall windows and format. If theres anyway I can just fix this that would be so much better.

Some help please I need this computer up and running asap!

does it boot on default settings? ie. not changing cluster size. If chkdsk found errors, I would download a ultility from the manufacture and (usually a bootdisk thing) and scan the HD to see if its defective.

ive had that problem on my laptop, well i rushed and i formatted which i shouldnt have. once i installed a new copy of windows it was all corrupted, it wouldnt let me delete, copy or access my stuff

dl this utility called HDD regenerator and it will fix ur bad sectors which scan disk can't. what i think is that the sector where the boot information is got corrupted and windows cant read it. it's worth a try

man you SOL man...good luck! >_<'

Hmm, well what I did is used the HDD with the fresh XP pro on it, got partition magic installed, and ran it to change clusters to 4k (just picked it because it was the max last time) and it booted perfect.

Since when cant you boot with >4k ntfs clusters? Can anyone else try this to see if Im just plagued?

Seagate has a utility called Diskwizard and u can get it at Seagate.com Theres a menu in there when u are partitioning and formating that allows you choose waht size cluster you want but only the cluster size appropiate for the format (ie NTFS 4k, FAT32 64k, etc).

Yeah but I need to format for that to work. I'll just play with partition magic