If its anything like this GX260 board I got, the comp can still at least boot.... I've not put mine in an actual different case, but you can remove the components and hook them up outside of the original case.

I don't see any reason as to why it wouldn't work in another case if you're gonna go to all the effort to mount it into standard cases. The only thing I'd worry about is the power supply pinouts, apparently Dell liked to use non-standard pinouts on their supplies back in those days. The IDE cables shouldn't really be a problem if there's enough room in the case to plug them in without putting too much pressure on the connectors. That being said, there's others out there with worse ways to connect them up 🤣

well I took it apart and put it in an old Soyo case I had sitting around and it fit like a glove. Everything lined up nicely. Just need to figure out the front connector pin outs. Anyone have any info on the 34 pin front connector?