IBM 3270 Hardware User's Manual page 121

9. Turn the system unit On
(I).
10. Watch and listen carefully for the three POST
responses.
D
Memory Test \ \
2
1I1"111I1I"IIIII~Dl
One Short Beep
3
I BM Personal Computer
Diagnostics Panel and
One Short Beep
5-6 Book 1 - 3270 PC Work Station User's Guide