None of the Intel processors based on socket 478 supports 64 bits.
This feature was implemented on Intel processors based on socket 775.
Also the motherboard that you are referring to, might not support Microsoft* Windows* 7 since that operating system was designed for newer motherboards. I would suggest contacting Microsoft* to confirm hardware requirements.
Check out spec code SL7PK, SL7E3. It is the motherboard you should be worried about.
In a word NO , you can't run 64Bit on a 478 board . Best to get new boards . there are still lots of 775 boards out there cheap .
Those are laptop CPUs?
Hmm, I've cross referenced those CPUs against the chipset, and non are listed as compatable.
None of the suggested cpus really are a good choice.
Jason's list (#4) is the newer series dual core that include mobile processors labeled Celeron and Pentium fitting socket 478.
The suggestion of SL7E3 is a Pentium 4 HT 2.8 - 32 bit only.
I too thought the old Pentium 4 Prescott - not HT- was 64bit, but turns out only if 775 version.
Upgrade to 775 board also requires DDR2 memory and a PCI-E video card if onboard not good enough.
My suggestion: ebay. HP business desktops Core2Duo at 99 cents to start from companies selling many per week.
You supply the hard drives usually.