I would HIGHLY suggest selling the CPU from it and buying a different model. I have four dual 867MHz MDDs where i work and all of them have crapped out. (though I did get to buy 2 quad G5s and now 2 3GHz Mac Pros to replace them!) I had a dual 867Mhz for personal use and the processor burned up (yes, BURNED. the white seal around the right processor was turned brown and the top was melted.) I have since put a Dual 1GHz cpu in there and it runs much cooler anyway. I also put a small fan right below the DVD drive, it seems to keep the side of the heat sink that the 120mm fan doesn't cool. The system runs at a Maximum temp of 115f. Anyway, just a word of caution.
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MacBook Pro, 2.2GHz SR Core 2 Duo, 120GB HD, 2GB RAM,
PowerMac G5, DP 2GHz, 2GB RAM, 1x500GB HD, Sonnet Tempo X4P, 2TB RAID, ATI 9650 256MB.