i286-Mainboard

From: Mario Premke <mapr0003_at_stud.uni-sb.de>
Date: Tue Mar 27 02:04:50 2001

> I hope you've tried the obvious, e.g. <F1> or <DEL> during the POST sequence to
> enter BIOS setup? The earliest PC/AT's used a setup diskette to do the setup of
> the CMOS-based parameters. That may prove to be a problem.

Yes, I get into the CMOS-Setup, but in there I cannot change the values
for memory and when I switch the power on the BIOS only tests the first
640Kb of memory ...

> To start out, I'd leave the "turbo" switch alone. However, there's usually a
> Turbo indicator LED that will tell you when you're in TURBO mode. If there's no
> TURBO button, there's probably a jumper connection available somewhere, and
> these connections are normally located in the lower left region of the board
> (assuming the power and keyboard connections are at the upper right, for
> reference. When you say "not available" do you mean you don't have one, or that
> it's not present/supported on the motherboard?

I put the board into a modern AT-Box - there's no turbo button or
turbo-LED.

> I'm curious about one thing ... Why is it that you believe it to be operable at
> 12 MHz? Is the CPU marked as such? Can you tell anything about the support
> chip set? I vaguely remember something about a Morse '286 around here

The clock on the board shows 24Mhz, so I assume the the CPU works at
12Mhz. I don't have the board right here and I cannot remember what chip
set is used.

> someplace. It's possible that there's a manual, but more likely it's a board
> that was hying about. I may not have it anymore, but you never know ...

There's a web-site mentioning the board, but the link to some manuals is a
dead link :-(((

Cheers,
Mario
Received on Tue Mar 27 2001 - 02:04:50 BST