ColorComputerStore Posted June 14, 2021 Share Posted June 14, 2021 I can't seem to find any documents related to a Zenith Data Systems ZMV-3926-GM. I'd like to learn about the motherboard. It got a ZMM149-P monochrome model with it. Thanks Carlos Quote Link to comment Share on other sites More sharing options...
wierd_w Posted June 15, 2021 Share Posted June 15, 2021 Is this your motherboard? (I see elsewhere that the model you specc'd is also listed as Z-320SX-40, which is what is pictured here.) Like most ZENITH systems I remember seeing from that era, it uses a backplane riser that is 90 degrees. Basically any old card can go in the riser. Quote Link to comment Share on other sites More sharing options...
ColorComputerStore Posted June 15, 2021 Author Share Posted June 15, 2021 Oh my! That's it! How did you find it? I'd like to learn more about it. This is a 386sx? What is the empty ic? For a math processor? What kind of RAM does it take? I'll attach the bios settings. Any place to download a newer bios if they exist? For RAM I saw two sticks in it. Didn't look at their label yet. Would be great to find the manual online. Thanks again. Quote Link to comment Share on other sites More sharing options...
wierd_w Posted June 15, 2021 Share Posted June 15, 2021 (edited) Well, just looking at it--- It has a 386 SX processor, and a LIF socket for QFD package 387 coprocessor. It uses a 3.6v lithium battery. (size 2AA) It has a maximum onboard RAM capacity of 32mb, assuming you stuff those 30 pin simm slots with the more expensive 4mb modules. I would suggest 1mb or 2mb modules though. (It probably only supports up to 16mb, with 2mb modules. This looks like a budget system intended for an office workstation type application. 4mb modules would be a crapshoot.) It has a chips and tech F82C836 (SCATx) chipset. (more information about the RAM capabilities can probably be found by looking up the chipset rather than the board) It has an integrated western digital disk controller, which handles both IDE hard drives and the floppy drive. (It probably has the 8gb limitation, and will likely need a DDO to use anything bigger. See Phil's computer lab for details) It uses a proprietary power connector. I certainly HOPE that your system came with the riser. You will need it to plug anything into its ISA bus. Assuming you do have it, you can plug any old ISA card into it. (sound blaster, AST ram expansions, etc.) Based on your description, you have 2 512kb 30pin simms installed, giving you a whopping 1MB total memory. (Basically, 640k + 384K used predominantly for shadow ram purposes. From the image of the BIOS, it is snarfing down 128kb of RAM for shadowram purposes, leaving 256k of extended memory left over.) That chipset is supported by a hardware UMB and EMS driver, if you dont want to use EMM386.exe to get access to upper memory blocks. https://www.pcorner.com/list/UTILITY/UMBDVR22.ZIP/INFO/ For BIOS upgrades... I have no idea where you would get one, but back in the day, there was a 3rd party bios company called MrBios. They had 3rd party BIOS images (and chips) for a number of systems. I will see if yours was listed. (looked, No dice. I would not recommend anyway.) Edited June 15, 2021 by wierd_w Quote Link to comment Share on other sites More sharing options...
ColorComputerStore Posted June 15, 2021 Author Share Posted June 15, 2021 Yes, there is a riser with two cards, one being a video card. The battery is a Dallas one and is dead. I'll need to drill into it's side and solder a cr2032 to it as those Dallas batteries/RTC are expensive to replace. This is a huge huge help. Next I need to figure out what version of DOS to install. Or if I go with Windows 95. Hmm. Thanks Quote Link to comment Share on other sites More sharing options...
wierd_w Posted June 15, 2021 Share Posted June 15, 2021 (edited) windows 95 will run very poorly on that system. It is the lowest tier 386 Intel made. (SX-25) It is also an old 30 pin SIMM based system, and will have dog-slow memory access speeds. All around, its a budget system from back in the day. It wouldnt have won any speed competitions then, and certainly wont now. I would suggest staying with DOS or DOS + Win3.11 I would suggest DOS6.22 I would suggest between 8 and 16mb of FastPage 30 pin simms. (8 1mb modules, or 8 2mb modules, all identical!!) I would suggest a nice jumpered soundblaster 16. (Avoid plug and play ISA cards like the plague!! They will almost certainly not work properly in this system! It predates PnP!!) Edited June 15, 2021 by wierd_w 1 1 Quote Link to comment Share on other sites More sharing options...
ColorComputerStore Posted June 15, 2021 Author Share Posted June 15, 2021 Btw... Is it better to use a Cyrix FasMath? https://www.ebay.com/itm/Cyrix-CX-83S87-16-KP-20-FPU-Ceramic-LCC-FasMath-Math-Processor-387SX-CX83S87-/392842294496?_trksid=p2349624.m46890.l49286 Quote Link to comment Share on other sites More sharing options...
ColorComputerStore Posted June 15, 2021 Author Share Posted June 15, 2021 5 minutes ago, wierd_w said: windows 95 will run very poorly on that system. It is the lowest tier 386 Intel made. (SX-25) I would suggest staying with DOS or DOS + Win3.11 I would suggest DOS6.22 Ok, DOS 6.22 is fine. I have a 100gb hd. Do U need to partition it to a smaller size? Or maybe better to use my ide2sdcard adapter. Quote Link to comment Share on other sites More sharing options...
wierd_w Posted June 15, 2021 Share Posted June 15, 2021 I would not steer anyone toward anything made by cyrix. The intel one I linked you to is the genuine article. Quote Link to comment Share on other sites More sharing options...
ColorComputerStore Posted June 15, 2021 Author Share Posted June 15, 2021 Just now, wierd_w said: I would not steer anyone toward anything made by cyrix. The intel one I linked you to is the genuine article. Lol. I was watching a nice benchmark video on YouTube and the Cyrix looked much nicer. Is it a compatibility issue? Carlos Quote Link to comment Share on other sites More sharing options...
wierd_w Posted June 15, 2021 Share Posted June 15, 2021 For a drive that size, you will *NEED* the DDO. Even with the DDO installed, DOS6.22 has a size limit of 2gb. THAT limit is imposed by DOS. You could maybe kinda-sorta get around it by abusing windows 98SE as if it were DOS (Using the EBD, and copying the C:\windows\command directory from a functional windows install to C:\DOS, and pretending it is "Dos 7" ahem) so that you can have FAT32 support, OR by going straight to FreeDos, and going that route. To set that up, you would need a bootable DOS diskette, *AND* you would need to have created the disk manager boot diskette. Boot on the disk manager diskette, and do the guided installation. It will set your BIOS to the correct custom geometry type for you (DONT TOUCH IT afterwards!), then install the DDO in sector 0 of the drive. The DDO will then intercept all BIOS disk calls, and will do software translation to handle large disks over 8gb in size. 1 Quote Link to comment Share on other sites More sharing options...
wierd_w Posted June 15, 2021 Share Posted June 15, 2021 Cyrix got a bad name for itself back in the day, by not being "completely compatible", and causing all manner of headaches. A specifically high profile instance, were Cyrix's 6x86 "Pentium compatible" processors. The FPU implementation in those would break HORRIBLY when trying to play Quake. They were almost without exception synonymous with "Trash." Quote Link to comment Share on other sites More sharing options...
ColorComputerStore Posted June 26, 2021 Author Share Posted June 26, 2021 I got MS-DOS 6.2.2 today so will try the installation. I'll check out the SB16 card. What do you recommend for a program launcher? I want to turn this machine on and have it autoexec a menu. And allow me to select all the programs I have installed so I don't have to type the programs names. Thanks Quote Link to comment Share on other sites More sharing options...
wierd_w Posted June 26, 2021 Share Posted June 26, 2021 For DOS? I was rather partial to Direct Access https://winworldpc.com/product/direct-access/5x Quote Link to comment Share on other sites More sharing options...
The Usotsuki Posted June 26, 2021 Share Posted June 26, 2021 DOSSHELL might've still been on the supplemental disk for 6.22, like it was on 6.20. Quote Link to comment Share on other sites More sharing options...
wierd_w Posted June 27, 2021 Share Posted June 27, 2021 dosshell is indeed on the suppliment disk for 6.22 I still prefer DA for a less busy menu. It supports sub-menus for categorization, and hotkeys. It will work on basically any PC with a BIOS and DOS. Customizable colors, etc. Quote Link to comment Share on other sites More sharing options...
ColorComputerStore Posted June 28, 2021 Author Share Posted June 28, 2021 My understanding with 6.2.2, you have a 2GB max partition and drive can only be 8GB. So if I put in a 80GB drive, does that still mean I can't format it into several drives of 8GB? I saw a utility by Western Digital that can get around the max size. Seemed like an option. Well, I tried to boot my band new 3.5" MS-DOS disks and it didn't work. So not sure if the floppy drive is no good or the Microsoft media is no good. I bought the disks sealed. When I finish moving, I will try to swap in some other floppy drives and disks to see what the route problem is. cheers Quote Link to comment Share on other sites More sharing options...
wierd_w Posted June 29, 2021 Share Posted June 29, 2021 Drive is 720k? Quote Link to comment Share on other sites More sharing options...
ColorComputerStore Posted June 29, 2021 Author Share Posted June 29, 2021 (edited) That actually very much crossed my mind. Its a 386SX so possible it is only a 720K drive. I will need to search online for 720K 6.2.2. drive images and give it a try. I have some 1.44 drives so if I need to, I can swap the drives. Edited June 29, 2021 by ColorComputerStore Quote Link to comment Share on other sites More sharing options...
wierd_w Posted June 30, 2021 Share Posted June 30, 2021 Your CMOS setup suggests it is 1.44mb. (a 720k drive would fail seek test on that setting, since it wont spin at the right speed, and wont seek to the correct track) Rather, I suspect you have a dirty or worn head. Alcohol on a soft cotton swab, with a gentle touch, both top and bottom head. A small dollop of new white lithium grease to the wormgear and sled rail. Quote Link to comment Share on other sites More sharing options...
ColorComputerStore Posted June 30, 2021 Author Share Posted June 30, 2021 That's solid advice. I'll give it a shot and report back once I finish my moving at the end of the month. (Machine is packed up) Quote Link to comment Share on other sites More sharing options...
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