The best CPU that can be officially used with your mobo (according to the asus website) is Q9650. With this mobo you can only do small overclocking. The G41 chipset is bad overclocker
On the other hand according to the link below, this mobo can support various modified 771 xeon. Sometimes it is necessary to modify the microbe codes of the mobo so that it works correctly. Read the indicated website carefully and act with caution.
This mobo can work with DDR2 or DDR3 memory alternately, but can not be combined. If you choose DDR2 choose 800 and if you choose DDR3 make sure they are compatible with this mobo, the most current DDR3 do not work well with this mobo.
https://www.delidded.com/lga-771-to-775-adapter/3/#asus
Currently most of...