Mid 2010 MacBook Pro hard freeze

Hi everyone!

This is my first time posting on here, so hopefully you can help me.

I bought my 15'' MacBook Pro in August on 2010. It never had any problems until a couple months back. Nothing I can remember happened to the computer that would have accounted for such a huge change in condition. At least, nothing that I can seem to remember/deem important. But now, it hard freezes all the time. The clock stops ticking, my mouse stops moving. Sometimes, sound from another tab will continue to play.

Anyways, it usually freezes when I'm browsing the internet (usually on Chrome, but sometimes on Safari as well). Most often on sites like 9gag, but definitely just casual browsing. It happens frequently enough to bother me (at least 2 times a day) because I need a reliable computer for school and work.

I've brought my computer into the Apple Store 5 times, and they don't seem to have fixed the problem.

I have cleared out about 130 GB of space on my hard drive. I have re-installed my operating system (Snow Leopard). I have put in new RAM. None of the Apple workers can find any problem, as they "cannot duplicate" the issue.

I just installed the update that came out in November 2011, but that doesn't seem to have helped because the computer just froze again.

Anyways, I thought I would turn to the vast support community I'm sure is out there. If you have any ideas, please let me know! I'd really appreciate it.

Thanks so much for your help 🙂