I've been having a similar problem. I have 2 hard drives, one with Vista (32 bit, not sure which version..) and the other with XP / 7 (ultimate x64). Until just about an hour ago, everything was fine, i had a multi-boot screen and could pick whatever OS i wanted and they would all boot. Just an hour ago, however, i ALT-Tabbed out of Mount & Blade to check facebook when the computer froze for the first time in well over three months. I didn't think much of it and pressed the little reset key, and the boot chokes on "Detecting IDE drives..." This happens a lot for some reason and is usually resolved by me wiggling the SATA cable coming out of the HDD (it's loose i suppose...).
When that didn't work, i began to worry and eventually got it to see both drives through mainly persistence. After that part, the computer checks for some other stuff, all of it works, and then instead of my 'select what operating system to boot to' screen, it just goes black. Eventually i get a blinking cursor in the top left, but no developments from there. I've let it sit for maybe 20 minutes and nothing happened. I obviously have access to another computer, but this $300 laptop is no substitute for my $1300 desktop.
I would appreciate any help i can get. The search terms in google are appearantly very similar to annother known problem where the computer gets to the windows 7 splash screen then goes black, but i'm not even getting there. I can't select boot into vista, xp or 7.
if this helps:
I went into the BIOS and changed boot order and got to the XP splash screen just fine, but my XP install is flawed and bugged, so like always it BSDs before loading. This is normal for my XP and probably isn't part of the problem. By booting to that HDD first, it circumvents the OS selection screen entirely, but doesn't get me into 7