HT12 286 - only 704kb of ram seen?

[Vein]

Hello,

I have an huge RAM issue with my 286 PC, it have HT12 mobo with 16mhz 286 cpu.
It only sees 704kb of RAM, 640kb of normal and 64kb of extended. I have removed ram from mobo, placed some simm ram, it has changed nothing, when placed half of memory (half of simm modules, or half of mobo chips, no difference), it sees 512kb, when filled all (simm and mobo) it is still only 704kb.
This mobo had battery leakage, that I fixed (needed rebuilding traces) so I belive, that could be an issue, but maybe you could point me to right direction? Don't know how is memory addressed.

Regards

 

[CarlosTex]

Have you installed a new battery? Use the external battery header if needed. I just fixed an Octek Fox II from corrosion and when CMOS values are lost BIOS only detects 704KB. Both my HT12 chipset 286 motherboards do this.

 

[PeterNC]

Some 286s need BIOS configuration set to have full memory recognized.