Vista - HELP! Vista keeps locking up on me!

Okay, so I've had vista (64bit) for almost 6 months now, and It's been working really well for a while, but now it's started to lock up after a few minutes of use. I've looked at a ton of different forums for some sort of help, but nothing I've tried has worked. When it locks up, I have to restart, the mouse, keyboard, or whatever fails to work. I just got new RAM (Mushkin extreme ddr3 1600), which I really hope I'm not going to have to replace.
the rest of my system: CPU: q6600 (intel), GPU: ATI HD 4870 1gb, MOBO: GIGABYTE GA-EP45T-UD3P HDD: WD 640 GB something or other, SB X-Fi Extreme Gamer, RAlink wireless internet card thingy.
Also, I CAN boot in safemode.
Please Help! This is killing me!

Hi Hedgy, welcome to the board.

What have you tried already that didn't help? Did it happen after you replaced the new rams? if yes, put the original rams back and try. And/or use minimal ram. Chkdsk? Have your tried to repair by restore system to an earlier restore point? Have you been using registry cleaner before it starts to screw up? Well, don't anymore.

How about open the case for a blow out with a couple of cans of spray airs. Main while, check your CPU heat sink fan is set securely since your problem could have been causing by overheating. Check your SATA cable and connection by disconnect and reconnect, shake and tug on the connecter at the HDD. Replace them with after market ones when you have a chance because the one comes with the mother board is usually problematic. Post back.

Hope this helps.