Major MacBookPro Overheating, over 100C

I am trying to fix my sister's 2006 MacBook Pro. It has recently developed some major overheating issues, causing frequent shutdowns and rendering it unusable. I have tried many, many things to fix this, but the most relevant piece of information I can give is that without the battery, the processor runs at 1GHz and .95V, and the temps are ~50C at idle and ~55C at load. With the battery, 2.16Ghz and 1.225V, and the temps are ~52C at idle and >100C at load. Does this mean anything to any of you? (before you ask, it's not dust, no runaway processes, etc.)