I'm into music production, and I'm redoing my studio. The computer I had is still good, except that it's got a slow CPU and too little RAM. It has an i7 Q720 GHz CPU and only 4 gigs of RAM. Is it at all possible to take it apart and switch the CPU with something a little faster, say around 2.5-2.8 GHz, and up the RAM from 4 gigs to 8 gigs? Would it be cheaper to build a desktop computer with better components? Also, I had a recent problem with it over heating because the fan stopped working. I got the fan fixed, but it seems to be having glitchy problems like programs take a long time to open and it lags every once in a while. Is this fatal to my computer, or can I get the parts replaced? Thank you.