Comment on 'boardswapping' as part of the computer culture.

[Tony Duell]

> 
> You know, that always surprises me - I'd expect board swapping to rarely 
> cause problems for reasonably modular systems (I can believe it with 
> such as DEC hardware though, where you so much as cough near it and 
> something breaks ;)

OK, one that bit me (it's not a board-swap, it's a module swap, but...). 
The fan in this PC's PSU decided to fail (bad bearings). I didn't have a 
fan in stock, so foolishly, I grabbed a 'spare' IBM-brnaded PC/AT PSU 
from the shelf amd swapped it in. It would be quicker, I thought, than 
extracting the fan from that PSU and popping it into the existing PSU. 
Result : the machine didn't power up at all. It turned out that the 2 
PSUs were of different makes (although both IBM labelled), and both met 
the IBM spec _which specifies a minimum load on some of the outputs). The 
'old' supply had been happy with less load than that, then 'new' one 
wasn't. And of course my modern hard drive didn't put much load on the 
12V line. It would have been quicker, and a lot less hassle, to just swap 
out the fan.

-tony