First post, by Mouldotron
I was hoping that I might ask you all for some advice in regards an old 286 mainboard that I've got here. It appears to be a Neat N286-5 with an AMI bios, four sip sockets (and the ones for the little 16 pin ram chips) and a 20mhz Harris CPU.
Only just got around to having a go with it. It does start and with a new external battery it remembers it's settings. It boots to windows 3.1 fine, although seems a bit sluggish.
Tried sysinfo.exe from Norton and it's getting a CPU benchmark of 4.4, whereas a 12mhz 286 should be getting 8.9 apparently. So, according to that, this 286 isn't firing on all cylinders. Like it's owner I suppose. Norton claims it's a 10mhz cpu but it clearly isn't. The crystal says 40.00 mhz as it should, and the CPU says 20.
There are no wires run to the motherboard (other than power) so I'm guessing one of the pin headers might be a turbo switch, possibly therefore OFF. But I've no manual and it doesn't say on the board.
The other problem I thought might be with the timing control in the bios. The memory is zero wait state, processor clock set to "CLK2IN", bus clock to "CLK2IN/2" and DMA clock is "SCLK/2". I don't really know if this is optimal.
Any help very gratefully received to get this old girl bubbling away full chat.