the mac mac pro 2.66 dual core 5gb of ram. 3 hardrives (1 250 2 750 gb) everything else stock. used for video editing and motion graphics. OK long story short. mac pro freezes all the time and crashes.(screen goes dark and says i need to turn it off) When it does this, computer cannot be turned back on right away i have to wait a good 15 minutes if i dont computer will physically turn on but nothing will appear on screen. Along with cd rom drive makes a ticking sound. i cannot determine any coicidences when it freezes. it freezes while running just about any of my daily used programs (fcs, adobe suite, itunes) or when im using computer or browsing a finder. it also comes and goes itll act up for a week then chill out for a month, however the past 2 months it has been rather continous with its problems. Another problem. One local mac specialists store and the apple store CANT find anything wrong with it. Both stores ran diagnostic test and their own tests on the machine (i am not aware of what any test done by both stores entails of) and they both cannot find anything wrong with the machine. SOOO apple care wont do anything cause technically they say its in perfect working condition but ITS NOT!!! i tried to work on the computer while i was in the store and guess what it didn;t want to freeze up on me. I got the machine back yesterday from mac store and have been out of a machine for over a month with no solutions and it froze within ten minutes of being in my office :-( apple store said it could be logic board,processor, ram, hardrive, or video card. well thanks for narrowing it down maybe its the case!!! i have tried the following things which all resulted in freezing. disconnecting any periphials(sp) usb, fire wire. installing more ram. removing apple ram and leaving after market removing after market and leaving apple ram fresh install of operating system 2 times. taking notes of each freeze in relationship to programs running and freezes while running various programs and sometimes NONE. installed new super drive. created new user profile disk permissions cleaned what i plan on doing. installing operating system onto brand new hardrive. purchasing new video card. after this i dont know what is really worth doing :-( other then buying new computer. it keeps me from working and is a royal pain in the ass. If anybody knows or has an idea please feel free to let me know.