simon@hpspwr.enet.dec.com (Curiosier and curiosier...) (05/20/91)
I need help in solving a serious problem: I replaced a 16 MHz 386SX board with a used 20 MHz 386DX, leaving all other hardware and software the same. Both the previous SX and the new DX have AMI BIOS's, date at about the same time (March - June 89). The rest of the system: 4 MB RAM, 512K VGA, RLL disk controller, 240 MB Maxtor disk with 1224 cylinders, partitioned with SpeedStor. Software: QEMM 5.12 with Windows 3.0; 512K PC-CACHE (*NO* Smartdrv.sys!). The 20 MHz board came from a known working PC, and did not have any problem. The other difference is that this board had an MFM controller while the new system has RLL. Problem One: The boot-up memory test counts to 4096. The BIOS screen that comes after this reports 640K plus 3072K extended. The board has 4 1x1 SIPP modules. Manifest also shows 3072K. The previous board showed all 3456K. Where are remaining 384K? Problem Two: Windows started to behave unpredictable. It lets me open a few non-Windows applications (sometime two, sometimes four, every time different), then, at an attempt to open another, the system goes to reset on its own. I opened three non-Windows applications, reduced them to icons, then tried to restore and got a message: "Insufficient memory, try to close one or more applications and try again" (or close to this). An attempt to restore any application from an icon in order to close failed because all of them produced the same message! I reboot the system, open Windows, run an application, close windows, and instead of returning to the DOS prompt, it resets the system. Any help will be greatly appreciated. --------- Leo Simon simon@pwrvax.enet.dec.com Who is not liberal when young, does not have a heart. Who is not conservative when old, does not have a brain. -- Attributed to many
bich@hpsciz.sc.hp.com (Bich Tran) (06/05/91)
As a designer of instruments cards for PC, PC hardware is nothing new to me. However upgrading from one system to another can be a very frustating experience ven for an experienced engineer. If you upgrading systems from the same manufacturer, chances of incompatibility is nil: when I uograded my Vectra ES/12 (286-12) to a QS/20 (386-20), it took me half an hour and no problem encountered. But when I upgraded my ES/12 to a 486 clone, it took me 3 full days to get it worked. I still have incompatibility problem to deal with like my COM ports are intermittently bad. Sorry for rambling around, the missing 384K is used for shadowing RAM: video ROM and system BIOS are loaded in this higher speed RAM for improved performance AMI bios just don't report it. If you disable( and you should not) shadowing thru setup you can regain this RAM portion for Exented. regards, bich