The only other idea I have is doing a fresh install of SL on the old 320gb drive, making a Time Machine backup of that, then put the new larger HDD in my MBP and then clone the old Snow Leopard backup from my external HD? Would that maybe work? All I want is a bigger hard drive with Snow Leopard running on it! I can't take it in to an Apple store because I don't live near one, and this honestly shouldn't be that difficult anyway. So I hung up and thought '***** it, I'll re-install the original HDD and see if it fires back up.if it does, it's obviously not a RAM issue.' Well sure enough, everything works fine with the original hard drive back in. That doesn't make sense, as I didn't even touch the RAM when I swapped out my HDD. So I called Applecare and the woman told me there is only one disc version of SL (10.6) and that three beeps means there's a RAM issue (she said it needs to be re-seated). Another person said he'd been trying to boot from the wrong version of SL and that once he got the right disc, it worked.

So I did some Googling (on another computer that works, obviously) and found that three beeps, for some people, means a RAM issue.

When I clicked on that to start installing SL, my MBP beeped three times, then paused, then repeated the three beeps. I went to boot from a Snow Leopard disc Apple sent me (I want to stay with SL) and I got the screen with the apple logo and then one with a little logo for the OSX SL download. Okay so I just replaced the factory 320gb HDD in my early 2011 MBP with a 750gb.

2009 macbook pro 3 beeps after idle