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You heard the beeps.  Obviously that is good.  What are the beeps telling us?

First, your motherboard is running.  Why the beeps?  Because switches 5 and 6 on switch block SW1 are both off, the motherboard's Power-On Self Test (POST) believes that an MDA (monochrome) video card is attached, and tries to initialise the card.  Because the POST can't find an MDA video card, it beeps the speaker (1 long, 2 short).

Second, the power supply is outputting at least two things: 1.  +5 volts; and 2.  POWER GOOD signal.


What Now?

Now, you reassemble your computer device by device.  Test the computer after you add each device.  At some point, the computer will stop working, and then you will know that the last device added is the cause of your computer's failure.

The first device to add should be your video card.  Before you do that, you will need to restore the settings of switch 5 and 6 on SW1 according to the type of video card you have.

5=OFF / 6=OFF	:  MDA card (monochrome)
5=ON / 6=OFF	:  CGA card
5=ON / 6=ON	:  EGA card or VGA card

So set those switches, plug in your video card, attach your monitor to the video card, and see if you get something displayed on the monitor when you turn on the computer.
If you have an IBM 5150 computer, note that you won't see a memory count (like the IBM 5160 displays).  Instead, expect to see a flashing underline cursor for the first minute.

After about a minute, expect to see/hear the A: drive being accessed.


If you didn't see a display AND you didn't see/hear the floppy drive being accessed (after about a minute), it is highly likely that your video card is the faulty device, either overloading the power supply, or faulty in some other way.

If you didn't see a display but you did see/hear the floppy drive being accessed (after about a minute), consider the following:
* The monitor may be the wrong type for the video card.
* You may have a faulty monitor.
* On the monitor, the brightness control or contrast control may be turned down too low.