Hello,\n\nI purchased a (supposedly repaired) AX4C Max a while ago. It runs fine\nwith a Pentium IV 3.06GHz Northwood (533FSB).\nHowever, I tried it with a 2.8GHz (800FSB) CPU, but it is completely\nunstable at this speed. CPU is fine. When I drop the FSB to 704MHz\n(4*176) the system is stable again, but not at any speed over that.\n\nIs this a well known problem? AOpen will not RMA this board and\nneither will my supplier, since I bought it with limited warranty.\nAOpen Support was unable to reproduce this problem on their system,\nbut their mainboard was from a newer batch.\n\nI tried changing RAM (5 brands), changed power supply (Zalman 400W,\nEnermax 265W, AOpen 250W), changing VGA card, etc. The only conclusion\nis, that the mainboard is at fault. This was also the conclusion of\nAOpen Support. I am currently using the mainboard with the 3.06GHz CPU\nagain.\n\nDo you believe a mainboard repair specialist could fix this problem? I\nmyself have no idea what to do about it or what the exact cause of the\nproblem is.\n\nAny recommendations are welcome!