I got a Compaq Portable III for very little money, mainly because it was considered dead.
Disassembling, cleaning, and reassembling it somehow brought it back to life, with the exception of the CMOS battery and the floppy drive.
I would not usually mention the CMOS battery, because it is obvious that batteries this old will be exhausted—assuming they have not leaked. However, the issue is worse on some Compaq computers because there is no built-in BIOS user interface. Instead, you have to run an MS-DOS setup program.
When the CMOS settings are cleared, the computer assumes:
- There is no hard disk.
- The floppy drive is a 360 KB model.
This is one of the rare cases where I purchased a replacement battery to avoid the hassle.
Floppy drive issue
The floppy drive had another problem: its spinning speed was extremely inconsistent, making it impossible to read even a single disk.
I had experienced the same issue with my IBM P70 and remembered that bad capacitors were the likely cause. However, when I opened the floppy drive, I thought I could only access the capacitors by disassembling the counterweight disk.
That turned out to be a bad idea for two reasons:
- It was not actually necessary to access the circuit board.
- I broke a screw in the process.
It was a left-hand-threaded screw, completely stuck, and I was not patient enough.
In the end, I had to purchase another floppy drive. This one works fine, except that it sees every disk as write-protected.
Another fix will be needed soon...