IBM ValuePoint 6482 machine type, L5F model number DX33. Playing with CMOS video to check a synch problem with a monitor. Now monitor blank, nothing period,even on known good monitor. Post 1,3,2 short beeps. How can I power-on reset/clear CMOS? Have removed CMOS battery for hours. Have disabled on board video and tried to use a video card to get back into CMOS. Still get Post 1,3,2 beep.