Consider installing a 120gb SSD for the OS (W7-WMC). Do a clean install of the OS; leaving the bloat-ware behind. Your WMC will run like a top with supper quick channel changes and snappy remote response. BTW:You will also enjoy rock-solid system stability.
3x HTPC's HDHR3-CC prime and Hauppaug OTA tuner.
Looking at a new HDHR4-CC that is due out mid 2013.