Hi Vogons

I've been busily restoring an old socket 7 machine I picked up. But I seem to have encountered an odd memory issue. Only 16 of the 64Mb is being detected.

The MB is as far as I can tell a PM-9000 Amptron. I was able to find some info online which showed jumper settings / memory configuration etc.. at http://stason.org/TULARC/pc/motherboards/A/AM … ml#.U4Xqxyi2UrY

I've looked high and low for a manual but so far I can't find one.

By my read populating bank 3 with a 8x64 sdram module should give me 64mb of memory. But irrespective of which bank I put it into at boot it only shows 16mb. Interesting the PC came with 16mb or so the bios claimed, in the form of what I assumed to be 2x8mb simms. I'm beginning to wonder if there is some error with the board.

So far I've looked for a 15-16mb hole setting but I can't find it anywhere. Might it be called something else? Or could it be set by jumper? That's not to say it does not exist, I just cant find it.

Also as far as I can tell there is no setting for OS/2 > 64 either.

The memory module I'm using is a infineon 8x64 sdram module synchronous @100mhz so I'm assuming this is a PC-100 era module which should be backwards compatible with a PC-66 board, which this "I think" is.

Well if there is any group of folk who can help me its you guys so any advice or direction gratefully received.

Edit: Just one other thing the board at boot complains about the cmos battery - only i cant actually find a battery! The most I can see is a Houston Tech RTC... is that what passes for the cmos in this board? And could it be that the inability to alter the bios due to the battery is what is causing the memory error?

Final Edit: Many hanks to all who took the time to view this post. Given the lack of progress I've made on this and it seems no one else had experience on this, I've decided to call it quits on this board and have bought another socket 7 board. For anyone interested this era of board uses an RTC block which contains an IC and a soldered 3V battery which you can get to by opening up the cover of the RTC. There are instructions online to remove this battery and solder a new one. This was most probably cause of the problem i.e why the additional memory was not registering. Thanks again to those who stopped by.
Thanks

Steve