afudos is considered the most reliable method, but ez-flash usually works fine too. Either of those is better than flashing from Windows.
I've checked the P5W DH Deluxe by Busykid, it said size mismatch too, but the person who flashed it said its ok after flashing and Vista activated. I just wondering whats wrong?
Yep! You r right! It is for checking separate SLIC.bin not for whole BIOS. I have miss understood info about this particular tool! Sorry for wasting your time!!
Did you clear cmos and load defaults?? Be sure the Cert and serial are correctly installed. No cracks of softmods.. The SLP is Dell.