4    IBM Desktop System HMM
External Ports
•
One multi-mode parallel port (25-pin D-type 
connector)
•
One serial port (9-pin D-sub connector)
•
One keyboard port and one mouse port 
•
Four USB ports (2 on port bracket, the other 2 on 
the front panel)
•
One Game/MIDI port (15-pin D-sub connector) 
•
Microphone-in jack
•
Speaker-out jack 
•
Line-in jack
•
One floppy port (up to 2.88MB, 3 mode support)
Diskette Drive
•
One external 3.5 “ drive for 2.88MB, 1.44MB or 
720KB diskette 
•
Two 5.25” drives for 1.2MB or 360KB diskette
•
Support 3-mode drive
Hard Disk Drive 
•
3.5-in., 1-in. height IDE drive. (3.5-in may be in 
acoustic mounting bracket), and 7200rpm. 
•
128 KB “look-ahead” cache memory inside the 
hard disk drive. 
•
Average and minimum 12 ms seek time, access 
time varies for the hard disk drive and the hard 
disk drive manufacturer.