The socket seems to be called "Socket P", "Socket M", "Micro FCPGA", or "Socket 478/479" (men does not seem to be the same as the good old P4), and I'm sure it goes by other names as well. The distance between the mounting holes is 42 mm or thereabout in both directions.
The MSI IM-GM45 motherbaord came with a Coolermaster EPN-41ELS-02-GP that sounds louder than my vacuum. Impressive enough of a 40mm fan to make that amount of sound, but not so fun to listen to.
![Sad :-(](./images/smilies/icon_sad.gif)
I'm looking foremost for something similar to the Coolermaster EPN-PBFSS-01-GP (sorry, but I'm not allowed to post links it seems), but it seems to have been withdrawn. But really anything that fits is ok - if it's too big, I'll just use the Dremel.
Cheers - Peter Hjalmarsson