Go for the newer P45 chipset. In most cases it OCs MUCH better than X38. If possible also consider X48.
For a CrossFire also look in to the P45-DS3R. For the two boards listed go with the ASUS. QX6850 for $250 s worth it imo.
Also just a note, you MAY run in to problem with the DDR2 1066 RAM, those RAM seem to have some compatibility issues.