Trouble formatting an MS DOS 486 DX 33Mhz

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Thread Starter
Mar 6, 2015
Hello all,

Something my friends champion me for is my ability to find errors that nobody ever knew existed, simply by touching a computer. That being said, I've also devoted a lot of time into learning various ins and outs and know enough to be able to put together a machine, diagnose, and repair a few, so I don't mind poking around in a PC.

I am having a bit of trouble with this one though. I am more used to plug and play, and have never worked on a DOS machine, but picked one up for that express purpose, I'm fascinated by it and want to use / upgrade a prebuilt 486 computer that can run DOS and windows 3.1 to mess around with. Here's the issue:

I had installed DOS on this computer and it worked for a time, then I put it away once I knew the OS was working. (My first install I didn't know what I was doing, and gave the BIOS a random number for drive parameters for the HDD, but oddly it worked) It sat around a bit, and I pulled it out again to work on it, and the first thing I did was remove the CMOS battery, it was corroding the motherboard. I haven't replaced it but I got the corrosion off. I booted it up, and it started giving me errors.

1st odd thing: both of the Floppy drive activity lights are always on. I am working on a theory that its something on the controller card, but I can't find anything wrong with the jumper settings. (my reasoning is that there used to be an error saying there was a controller card failure, but that doesn't show up anymore soo...)

2nd odd thing: I have everything configured the way that (to the best of my knowledge) it should be set (including the hard drive bios parameters this time, stupid me). When I boot up the computer, it goes through its paces and the prompt displays this:

Insert BOOT diskette in A:
Press any key when ready

I pulled out my windows 98 machine (Pentium 1) to make a DOS boot disk, and inserted it into the 3.5" drive, which when I first installed dos and win 3.1, it worked fine as the A drive. I struck the key, it waited for a moment, only to have it come up again. It's like the prompt is caught in a loop from the minute I boot into it, and I can't access any of the drives, nor run a floppy disk. I am completely stuck, please help me if you can, I'd really appreciate it because I am dying to see it working.

Here are the specs and the configuration.
Motherboard: 16 bit ISA with VLB connectors, manufacturer unknown. Marking found was Made in taiwan, model number likely ASY 01-00231, but haven't had much luck with any numbers I got from it on google.
Bios chip: American Megarends AMIBIOS 486DX ISA BIOS AA5642987

Processor: Intel 80486 DX, 33 Mhz
Numeric Processor: Present
Cache: 256MB (likely L2 from the chips on the mobo)

Floppy Drive A: TEAC FD-235HF 1.44mb drive (Edge connector>IDE)
Floppy Drive B: TEAC FD-55GFR 1.2mb drive (IDE>IDE) (Both floppy drives have jumper settings, but I haven't looked into that yet. They're set on the same data cable)

HDD 1: Seagate ST3144A [Parameters: 1001cyl, 15 Heads, 17 sectors, 130.7 MB, no WPcom or Lzone, a website I went on said to leave them set to 0]
HDD2: Same make, model, and parameters, lucky for me. They're connected and jumpered in Master/Slave Relation on an IDE cable to the controller card.

COM, controller, and IO card 1 (The one I am more worried about) Generic DLW 200, 16 bit ISA. I found a schematic of it and it looks like all of the jumpers are in place properly.
Main Chip: Inbond W83757F
COM card 2: Unsure, tons of serial numbers, and not in use at the moment for anything except as an extra card. It's an 8 bit isa, but here's what I got off it if it's relevant
Startech st16c552cj
PN 4196

Graphics card: 16 bit VGA
Trident TVGA8900CL

DOS version I intend to run: MS-DOS 6.0 with windows 3.1

I realize this is a very long read, and if you've stuck around till the end, thank you in advance, and I would appreciate any help at all with this.
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