Does anyone remember building AT form-factor PCs?

VirtualLarry

No Lifer
Aug 25, 2001
56,331
10,043
126
I remember snapping the plastic standoff pieces to the mobo, and then there were these hook-like plastic pieces that went along the far edge, and you would drop the mobo in and slide it into those hooks.

But what I don't remember is, was there a screw somewhere to fix the motherboard in there? I don't seem to remember.

I also remember having to wire up the front-panel switch to the four wires coming from the PSU. Those wires were "hot" AC wires, directly from the wall, so you had to be careful with them. I made the mistake (never repeated!) of leaving the PSU plugged into the wall, ostensibly to ground things, when I was wiring up the front-panel power switch. Well, somehow, I zapped myself. Good times. :(

And then there were those strange "P8/P9" PSU connectors from the PSU to the mobo. Two connectors, that plugged in next to each other. I just remember having to match the colors in the middle. I don't remember if they were black or red.

I also don't remember all of the voltages that those connectors carried. I don't think that +3.3v was brought to the mobo in those days. Probably just +5 and +12v. Maybe -5 and -12v too.
 

bononos

Diamond Member
Aug 21, 2011
3,889
158
106
There were a few screws along the edges.
I can't remember the 4 wire AC connector from the psu.
P8/P9 are next to each other as you said, not sure about the colours, you could try looking for pin1 and match it up to the coloured wire for both.
P8 has one wire position that is unused and there is no 3.3v like you said, just + and - 12v and 5v.
 

Piano Man

Diamond Member
Feb 5, 2000
3,370
0
76
And the AT Power On/Off switch that clicked? I remember modding an old Gateway P5-60 (AT) tower to fit a PIII Mobo/cpu (ATX). It wasn't pretty, but it worked.
 

bryanl

Golden Member
Oct 15, 2006
1,157
8
81
The very first IBM PC/ATs and AT clones had no setup program in BIOS but required loading it from floppy. So we were under strict instructions to always have a setup floppy nearby, including one in an envelope taped inside each machine.
 

WT

Diamond Member
Sep 21, 2000
4,818
59
91
AT ?? I still have one. I keep it hidden behind the furnace so my wife doesn't see it. PC Chips 726MRT board. Amazing that it still may even work !

Atcase.jpg
 

Smoblikat

Diamond Member
Nov 19, 2011
5,184
107
106
I remember snapping the plastic standoff pieces to the mobo, and then there were these hook-like plastic pieces that went along the far edge, and you would drop the mobo in and slide it into those hooks.

But what I don't remember is, was there a screw somewhere to fix the motherboard in there? I don't seem to remember.

I also remember having to wire up the front-panel switch to the four wires coming from the PSU. Those wires were "hot" AC wires, directly from the wall, so you had to be careful with them. I made the mistake (never repeated!) of leaving the PSU plugged into the wall, ostensibly to ground things, when I was wiring up the front-panel power switch. Well, somehow, I zapped myself. Good times. :(

And then there were those strange "P8/P9" PSU connectors from the PSU to the mobo. Two connectors, that plugged in next to each other. I just remember having to match the colors in the middle. I don't remember if they were black or red.

I also don't remember all of the voltages that those connectors carried. I don't think that +3.3v was brought to the mobo in those days. Probably just +5 and +12v. Maybe -5 and -12v too.

There was no 3.3, i beleive that was implenented when SATA became standard.