Computer-related forums (or newsgroups, which aren't as as useful, for it, as they used to be) can be wierd. It's hard to predict when they'll just ingore you, or why. Don't wanna tack your problem to the end of a solved thread, though - your problem is gonna be different, and they've already finished with the thread anyway. But, yeah, sometimes you won't get helped, no matter what, and meanwhile they'll swarm all over the guy next to you.
What you want is a single bios beep, right at the beginning. No beep means the motherboard ain't working (might not be permenant). Multiple beeps mean something is up, but you can probably fix it. Helps if you can google up a chart for that BIOS's beeps.
Since you're in the troubleshooting phase, it's best (data safety) to leave the drives-with-data out of the loop (unless all the data is backed up). On the other hand, if you fix a problem elsewhere, you could put everything together and just try it.
A SATA->IDE adapter, that makes sense. But it's also a potential point-of-failure, so that's another reason to leave the IDE's off for now. Also, that buisness about setting the IDE drives to master - manufacturer's like to give simple, non-threatening instructions that sound like no-compromise, but which may or may not have a hard reason behind them. If you dug into their faqs, you might find there's a lot of leeway, and it depends on the partiiculars. In any case, if you have a WD alone on its cable, you have to set it as single, or things will get screwy - and the adapter is probably fine with having a single set as single.
I don't normally buy hardware for people, so I'm not that kind of go-to guy. But us go-to guys have a tough time keeping up. Things get past us. So no reflection on him. A single-core
would be in heaven with a 400W.