Google says the board supports MMX CPUs. The BIOS date is also after the release of the MMX CPUs.
I just wonder about the jumperless because of this: http://web.archive.org/web/20040619192454/htt … er_Settings.htm
and this: https://th99.bl4ckb0x.de/m/P-R/33916.htm
I don't know if "Explorer 2 (P5I430VX-250DM)" or "P5I430VX-250DM EXPLORER II" is different from "P51430VX/250DM Explorer II", I'd say it's probably the same board.
Could you compare your board to the TH99 schematics?

blacksvk:
what CPU was installed before?

Maybe reset bios? Also new jumperless boards sometimes didnt detected new cpu - try holding J key when starting computer - this should tell bios to redetect CPU and memory. Think there was also other key, but cant remember which one (F or G).

idspispopd wrote:

Google says the board supports MMX CPUs. The BIOS date is also after the release of the MMX CPUs. I just wonder about the jumper […]
Show full quote

Google says the board supports MMX CPUs. The BIOS date is also after the release of the MMX CPUs.
I just wonder about the jumperless because of this: http://web.archive.org/web/20040619192454/htt … er_Settings.htm
and this: https://th99.bl4ckb0x.de/m/P-R/33916.htm
I don't know if "Explorer 2 (P5I430VX-250DM)" or "P5I430VX-250DM EXPLORER II" is different from "P51430VX/250DM Explorer II", I'd say it's probably the same board.
Could you compare your board to the TH99 schematics?

Yes, it's same board except cpu jumper headers are missing. (I think there are 2 versions: jumperless SpeedEasy version and normal version, but both versios have same PCB).

kixs wrote:

blacksvk:
what CPU was installed before?

Intel (P54CS) Pentium 150. I also tried IDT Winchip C6-200, which is working OK.

vlask wrote:

Maybe reset bios? Also new jumperless boards sometimes didnt detected new cpu - try holding J key when starting computer - this should tell bios to redetect CPU and memory. Think there was also other key, but cant remember which one (F or G).

I tried holding J, F and G but without success. I also tried reseting CMOS and nothing...

Happened before.
P5I430VX-250DM Explorer II - problem

Does it still work with the old CPU?

So it's jumperless but are there settings in the BIOS?
If so then.
Put old/working CPU in.
Go into BIOS and change settings for new CPU.
Turn it off - swap CPUs.
Now see if it will boot.
.

PCBONEZ wrote:

Happened before. P5I430VX-250DM Explorer II - problem […]
Show full quote

Happened before.
P5I430VX-250DM Explorer II - problem

Does it still work with the old CPU?

So it's jumperless but are there settings in the BIOS?
If so then.
Put old/working CPU in.
Go into BIOS and change settings for new CPU.
Turn it off - swap CPUs.
Now see if it will boot.
.

Yes, old CPU is working fine. Yes, there are setting in bios, look: http://i.imgur.com/yT54YS7.jpg http://i.imgur.com/PqfKX8M.jpg . But I cannot set dual voltage option (probably because single voltage cpu is installed).

Also, I found out, that there are multiple versions of this board. According to archived QDI site Version 2.0 have some jumpers for choosing single voltage/dual voltage option (I think version 2.0 is this one: http://www.uncreativelabs.de/th99/m/P-R/33917.htm ). My board is version 3.0 and do not have theese jumpers (bios shloud be able to detect it automatically). Also archived qdi product page claims that this board support MMX CPUs....

Another interesting fact is, that my motherboard has JS3 jumper between Socket 7 and Cache slot and cannot find any information about that jumper. Any clues? Image: https://imgur.com/AjCFTzT

blacksvk wrote:

Yes, old CPU is working fine. Yes, there are setting in bios, look: http://i.imgur.com/yT54YS7.jpg http://i.imgur.com/PqfKX8M.j […]
Show full quote

PCBONEZ wrote:

Happened before. P5I430VX-250DM Explorer II - problem […]
Show full quote

Happened before.
P5I430VX-250DM Explorer II - problem

Does it still work with the old CPU?

So it's jumperless but are there settings in the BIOS?
If so then.
Put old/working CPU in.
Go into BIOS and change settings for new CPU.
Turn it off - swap CPUs.
Now see if it will boot.
.

Yes, old CPU is working fine. Yes, there are setting in bios, look: http://i.imgur.com/yT54YS7.jpg http://i.imgur.com/PqfKX8M.jpg . But I cannot set dual voltage option (probably because single voltage cpu is installed).

Also, I found out, that there are multiple versions of this board. According to archived QDI site Version 2.0 have some jumpers for choosing single voltage/dual voltage option (I think version 2.0 is this one: http://www.uncreativelabs.de/th99/m/P-R/33917.htm ). My board is version 3.0 and do not have theese jumpers (bios shloud be able to detect it automatically). Also archived qdi product page claims that this board support MMX CPUs....

Another interesting fact is, that my motherboard has JS3 jumper between Socket 7 and Cache slot and cannot find any information about that jumper. Any clues? Image: https://imgur.com/AjCFTzT

I had a look. At first I thought it may have something to do with the Coast module, but couldn't it also be the i/o voltage setting? (this will either be 3.3v or 3.52v). But I don't know, I tried comparing it with the other AT QDI s7 boards but the ones I checked didn't seem to have this jumper either.

Could also be that your jumper is present on more QDI boards, but the ones who made th99 simply didn't include it (this has been seen before, not everything about th99 is complete, some things aren't even correct but that's not really relevant here).

As I recall some boards had a jumper to switch between single and dual voltage CPU types.
Maybe that's what JS3 is.
.