First post, by Charleston
- Rank
- Newbie
Got this board on ebay, identified it, thought I was clean and good to go until I tried to setup my jumpers and pop in the dx4-100. I get no boot, no beeps, nothing. I spent hours working with the thing and as a last ditch effort set all the jumpers to as they were when I received the board (using an image from the listing) and popped the 50mhz sx2 back into place. Many of the jumpers were set under "Cyrix CPU" and not dx2 or other as I imagined they would be but apparently this worked.
(Note that when I replace the sx2 with the dx4-100 I get a boot but it locks up after several seconds)
https://www.elhvb.com/webhq/models/486vlb3/v4p895v1.htm
Fast forward and I've gotten to the point where I can change almost every jumper to the proper locations after much trial and error and get a boot from the dx4-100 (using the 50mhz clock which causes the system to freeze and give a 7 beep post after a minute) and the only jumpers I can not change whatsoever without going back to a black screen of nothingness are:
- JP1 (switches to 3V, tested the regulator and I get an output of 3.6 through my dmm so I'm at a loss here)
- JP43 (Switches the clock. Every manual says something different but it's just 2x, 2.5x, and 3x for dx4s)
- JP 38 and 39 (These two set the clock speed. Typically both are closed which gives 50Mhz, but with even one of them open to give either 25mhz or 33mhz I get absolutely nothing)
Changing any of these in any way at all leads me to nothing. As far as I'm aware I've done every possible config.
I'd really appreciate any help at all. You would think this board would be easy when it has everything labeled all over it.
Edit: I don't actually know if the 50mhz is a sx2 or a dx.