Hello, I have an old ASROCK 775 dualvsta and I am looking to replace the CPU. A new PC is not in the budget but want to speed it up. Currently only have a P4. I flashed it with the pctreiber Bios 3.19a. The site says it "Add support for E-0/R-0 Wolfdale CPU (Pentium DualCore E6300/E7600 supported!)" Does this mean any e series wolfdale core or just 6300/7600. I found a good deal on a 5700 and 6600.
According to the CPU support list the 65nm Conroe based Core2Duo line is the best CPU that board will support. I would look around for an E6600, I had one for a few years. Great chip in it's time. Really any of the Core2Duo line will be a huge upgrade from a Pentium 4.
I would not try the newer Pentium dual core 45nm Wolfdale based chips. That board has a Via chipset and I doubt the newer chips would work. You will also have a hard time overclocking with the Via chipset.