evasive wrote on 2020-05-23, 09:34:
If you could do that with frying any CPUs and get the bus speed + multiplier jumpers documented we can put this board into the Vogons TH99 revamped project. That would be very nice to say the least. I guess the last gif picture I posted wasn't a match either then?
Not much unfortunately.
As far as i can tell, bus frequency matches : after POST , it recognizes my cpu as am486 enhanced with 120mhz frequency. I'll need to tinker more with this jumper(and also the cache), maybe tomorrow.
Voltage mixes up your last picture and the F4DXL-UC4 manual : i don't physically have all the jumpers shown in your last gif, but i have the voltages correctly listed(3.45,4,5v). On the other hand, i have the correct jumper settings in F4DXL manual, but it lists3.3 3.45 and 5 v ( i get 4v instead of 3.3v in mine, if i close jumper 23)
Cpu selection is the big ??? .
I actually have settings for 'p24d 'from the f4dx manual,(when i bought this card i found those jumper settings already there) . I've changed em once with some setting i found on the net (TK8498F / F4DXL-UC4D) because they had settings for amd dx4, and the mobo booted anyway, without difference from the previous setting.
By the way, i've resolved the voltage issue: found the voltage regulator datasheet, had a test scheme and the formula to calculate resistance needed for a certain voltage
I've found R1 and R2 on the mobo,r1 is 680 ohm and r2 is 1200 ohm, VREF was 1.25. Used the formula to calculate r2 if i wanted 3,3v as Vo instead of 3.45. The correct value is 11oo ohm. So i added a 12k resistor in parallel to the 1.2k to correct the issue.(it's soldered on a jumper so i can flip it away if i need to get another voltage)
Then i checked the output and...
well, maybe it's a little bit too precise now! I've also checked all Vcc pins on the socket , they were all 3.3v and in the right spot.
i've also added a little heatsink, to the regulator, just to be sure it doesn't get too warm