Customer calls with a PC that is freezing (at random… every few minutes, with no apparent correlation to a possible cause, except she replaced a faulty monitor a few days prior to this problem starting).

I thing its possibly a heat issue, as I have seen a few PCs struggle with Brisbane’s summer heat & poor air circulation due to dust & poor case design.

I cannot make the PC freeze (windows 98 running an amd athlon 750Mhz in a HP case), so I open it up & clean out the dust (it’s not overly dustly), but I cannot cause a lockup… I try running an openGL screensaver, but still no lockup.

I suspect it should all be fine, but while on my way home, the customer calls & says it has locked up again… and given that she needs it for the weekend, I return with a few spare power supplies & an old spare PC.

Changing the power supply doesn’t help, so I start to suspect the motherboard (the PC is about 8 years old).

So I place the HDD into the spare PC that I took with me & fire up win98… after windows “discovers” all the new hardware, it’s back up & running… at this point (after over 2 hours of working on cramped PC cases, I suddenly remember one of the windows98 mistakes I made many many years ago: activating the DMA setting in the device manager properties for the disk drive often causes random lock-ups).

I check it out, and: yes, DMA is activated… I switch it off & ask the customer if anyone with technical knowledge has used the PC (answer is no)… Given that the PC is running, I decide not to waste too much more time tracking the exact cause of the problem.

Customer assures me she will call if the PC gives any more problems.