DAC_MODE
uint32 tmp = INREG32(DAC_MODE) & (H_SYNC_OFF | V_SYNC_OFF);
uint32 dacMode = INREG32(DAC_MODE) & ~(H_SYNC_OFF | V_SYNC_OFF);
OUTREG32(DAC_MODE, dacMode);
uint32 dacMode = INREG32(DAC_MODE) & ~DAC_MODE_2X;
OUTREG32(DAC_MODE, dacMode);