Multi-threading is becoming more present in modern games and with a Q9300 its a 45nm so virtually the same as the E8400 in terms of manufacturing process therefore it should reach similar clocks (less 100-200mhz due to the heat from the extra cores).
"Just set up a Asus P5Q + Q9300 + 4gb DDR2 800"
He already owns it which would make it an ideal platform to add a gpu to and convert into a gaming pc. Coding and programming doesn't normally need such hardcore hardware as a gaming pc.
kbaird what OS are you running atm? what resolution is your monitor? do you have an aftermarket cpu fan?