HDD problems after Chipset Fan replacement EP-9NPA3-Ultra

Yo
I have an older system I built 4-5 years ago for my father-in-law.

We replaced the PSU with a used one a while back because the PC was just shutting down randomly. That fixed the problem for a year or so.

It started shutting down randomly again, so he shipped the PC back to me to investigate.
Went ahead and put a brand new Antec 650W PSU in, and I also wanted to replace the Chipset fan/heatsink because it was making a terrible racket. I got a Zalman passive chipset heatsink.

I was a little rough getting off the stock chipset fan/heatsink. Rather than take the whole board out and carefully push the pushpins thru, I just yanked the sucker off from the top. No visible damage was done.
I carefully scraped off the thermal grease with a razor and also carefully wiped with rag and Acetone.
Installed the Zalman heatsink per instructions with thermal grease with no problems.

I coincidentally had unplugged the SATA cables from the board during install cuz they were in the way. Apparently when I plugged them back in, I crossed them (was running RAID stripe on 2 drives). . the computer would not boot to windows, and the RAID BIOS did not see the array. I realized I may have crossed them, so I switched the cables back. The RAID BIOS then saw the array and it started to boot to Windows but would crash.

I've since given up and was going to wipe the drives and reinstall Windows (XP home SP2).
However - Windows Installation CD nor DBAN (Darik's Boot and Nuke) will not format either the 2 original HDDs OR two other SATA HDDs I have from an old PC that had been DBAN'd.

Why won't anything work to wipe these HDDs?

Did I damage the chipset (and therefore the Nvidia HDD controllers) somehow in replacing the cooler?

This has really really got me stumped. Please help!

Try disconnecting everything and start over from scratch.

One way to remove a heatsink that has been installed for a while, is to run the computer for a few minutes so that the CPU/heatsink warms up a little. Then try to take off the retaining screws and gently twist the heatsink off the CPU.