From the top of my head since the mobo is at my office, there are jumpers for:

- cpu voltage (5v , 3.3v , 3.45v and 4v)
- cpu type (DX2, DX4, P24 and so on)
- fsb jumpers

and a set of unidentified jumpers on the RAM/SRAM area , no clue about them :\

Hi Keropi, have you still got that mobo?
Do you want me to scan the manual? I got one 😜

And it's a full 54 page fattie! 🤣

Really? I have kept it as my single 486 mobo , if you could just scan the pages that offer jumper info ( or anything useful other than specs or how to access bios) I'd be grateful 😀
I still don't know what several jumpers are doing on this, it just works as-is from the previous owner...

Alrighty, later today you'll have it!

awesome , thanks in advance! 😊

Here you are! It even has the chipset pinout, benchmarks and compatibility add-on card chart! 😲

Todays' manuals are so boring...

https://dl.dropboxusercontent.com/u/60581885/J%20manual.rar

great!!! thanks for taking the time to scan it! appreciate it! 😁

It costs nothing 😁
Now I'm happily throwing it in the bin, it's fulfilled its purpose 😜
Just make sure to preserve the data (or send at mbarron), because in some days I'll also delete the file from dropbox!

heh
for now it's uploaded to vogonsdrivers 😉

Hi everyone

Sorry for reviving an old thread. I just recently aquired a similar mobo (Jetway J435-A).
I noticed that it had some printed information on the PCB about the jumpers
Keropi mentioned that are also not included in the scanned manual.
These are for onboard L2 cache and goes as follows :

....................... JS1 JS2 JS3 JS4 JS5 JS6
1M....................1-2 1-2 2-3 2-3 1-2 2-3
512K.(single)...2-3 1-2 2-3 1-2 1-2 2-3
512K.(dual)......1-2 1-2 2-3 1-2 1-2 2-3
256K.(single)...1-2 2-3 1-2 1-2 1-2 2-3
256K.(dual)......1-2 1-2 1-2 1-2 1-2 2-3
128K.(single)....1-2 1-2 1-2 1-2 2-3 1-2

I was able to test the above configurations for dual banks using chips for 1M cache.

Overall, I am quite happy with this motherboard, very feature rich,
same or better than the famous 486VLB ASUS one (although mine has a VIA chipset and not the SIS one).
It has 1MB L2 cache, 128MB RAM, onboard voltage regulator, 2VLB with bus master on both,
support for FSB up to 50MHz, onboard IO & VLB EIDE and PS/2 Mouse!!!!!

On the downside, it doesn't have a setting for CPU multiplier, so my 5x86 is stuck at 3x
I need to find a way to ground that R17 CPUMUL pin or use an interposer..... 🙁
Also, beware!! My BIOS has a lot of issues (Y2K, Year 2094 issue),
including sometimes not reporting correctly CPU speeds AND 0KB L2 CACHE!!!

So, if you test these jumper settings DO NOT TRUST YOUR BIOS!!!
It will only sometimes report 256K or NONE.
Also, EVERY utility I tried (both on DOS and Win9x) reported that
I have 0kB L2 Cache, although I could tell the difference when I enabled it.
To verify my setup, I ran SPEEDSYS which checked memory transfers and
correctly found the amounts of L2 cache I had (see pics below).

Keropi, is it possible to upload your BIOS here, since yours might be a later version (mine is J435-A)
I suspect all these (or some) BIOS issues might be fixed on yours.

PS: @GeorgeMan: Thanks for scanning the manual 😀