I have a Dell computer with a BTX motherboard with pentium 4 in a 775. I really have 2 questions -
1. Are all socket 775 motherboards compatible with wolfdales? I know that there's a good chance it might be compatible, as I had the computer built in 2005, and I was offered the choice of a core 2 duo.
And if I decide to buy a new CPU, making sure of the above ---
Will the stock HSF fit on a BTX motherboard, or do I have to buy the intel BTX fan?
Yup, that stinks for you. Early 775 boards won't work with latter CPUs for a variety of reasons. One, supporting the FSB speed. Some boards will overclock the memory controller on the northbridge to support newer chips, but most won't. More importantly, Intel wasn't very consistent with the pin layout as they released new CPUs, so the boards are not able to supply power and information to the CPU as the CPU expects. That's because the CPUs out at the time such boards were designed did not use some of those pins or used them differently.