I have an old MacBook Pro (mid-2008, 15 inch). Apple replaced the main board and I upgraded RAM and replaced HDD.
When I use OSX on it, it freezes randomly and I have to reboot it.
I installed Ubuntu on it, it never freezes but sometimes it hangs for a while. And the other day, I copied many files to it over from network and the files are set read-only mode. I can't delete them even with sudo.
When I use the MacBook, usually it's very hot.
It might be too old to be useful now. However, I like it very much especially the keyboard (the metal one).
What do you think cause the problem? Is there a cheap way to diagnose it to find the problem part? I wouldn't mind spending 100 bucks to revive it.