my DSR 704 is 9 years old. Its been upgraded twice. This time it has a 160 gig Magnetic Data drive installed. The second tuner has had issues with pixelation, and loss of signal. I just kinda lived with it. The other day, during a particularly hard day for the drive, it crashed. I was recording two seasons of a show, which was running back to back. About halfway through it began behaving strange. screen said to insert a valid access card a few times, then went away. When I hit guide, I would get the guide, but the pix was frozen. I tried to move around on the guide, it would go away. When I tried to reboot, no dice. A 3rd time and it says, internal temp too high, shut down to prevent damage. Trying to determine...HD, software, powersupply, or worse. Please help me not to over spend what little money I have.