I wanted to get some opinions on the GPU heat sinks. Is the 1.0 fan and heatsink better at cooling then the 1.1 and up passive heatsink? I always felt the passive was better. I have 2 chihiro arcade mother boards and 1 is a 1.1 (AT style single row PSU connector) and the other is a 1.2 or 1.3 (ATX style PSU connector) and both have a GPU heatsink from the 1.0 and fan and they connect to the motherboard exactly like the 1.0 motherboard. So my point is that they must have a reason for using that GPU and fan setup on those boards. Maybe I was wrong about the passive heatsink.
one would expect the Chihiro boards to be operating for large part of the day hence the extra cooling , unlike most home based xboxes
Lapping the heatsink and applying something better than whatever Microsoft included will do a lot more for cooling than using the 1.0 heatsink with a fan strapped to it. Personally I use IC7 Diamond thermal paste as it performs better than AS5 in my experience. Some find it a PITA to work with due to the fact its consistency is more akin to that of cooling hot glue than peanut butter. Find something that you can strap in there with a copper base as well. Regular XBox heatsinks are pure aluminum blocks and copper transfers heat better. Downside is that unless you modify the heatsink to fit or custom build one you won't be able to just drop it in and use the stock restraints.
After you mentioned lapping the heatsink I looked and you are right. They are not that smooth at all. I will get that heatsink to shine! I will look into cooper heatsinks this weekend. It should not be to hard to get something close already and straping it down should not be the hard either.
