Hi I recently replaced my hard drive and got everything back up and running. After a few days, when I went to turn on the computer, I got no signal to my monitor. The power turned on and fans kicked in etc, but no beeps and no signal. I've tried removing/replacing/cleaning everything but no change. I also removed the battery for 15 minutes and then put it back. No change. I'm thinking it's got to be something up with either the motherboard, CPU or PSU (even though I do get power) but I'm on a tight budget and don't want to buy replacements unless I'm sure it will resolve the problem. Any suggestions for how I can either fix this or at least determine exactly what needs to be replaced?