Hello. Recently my Pentium II Motherboard Tekram P6F40K-A5 stopped posting. No beep, no video. It happens after i took out processor from the slot for mounting fan. I have applied contact cleaner to slot, change Ram, graphic card, CPU, reprogram the bios, but nothing helps. Power go on, lights are up, but no post. I did some measurements in voltage on three mosfets which are presents on the motherboard and i assume that one of them have insufficient value.
On the attached photo there is:
1. Mosfet number 1 , looks like CPU core voltage. After I insert Klamath CPU it goes 2.8V and 2.0 V with Deschutes CPU , so it looks correct.
2. Mosfet number 2, looks suspicious for me . It is I/O Voltage or something else? Without CPU it has 4,9 V, alter i Insert Klamath it goes down to 4,6V and with Deschutes it has 4,7 V. Doesn't it shoud be stable 5V?
3. Mosfet number 3 , has stable 3,3 V. It goes to PCI. This board has correct implementation with 3.3 V PCI (Chinese Rage XL PCI works fine without mod 😀)

Can someone confirm my thoughts that mosfet number 2 is ging to low with Voltage? Does recaping help in this situation? Caps looks good, those are Sanyo 6.3V 1000uf.

PS. I have ordered post analyzer card 😉

Update:
Finally i have got a post analyzer card. Unfortunately it reports ---- code and the RESET line is constantly light up. I have put out the bios chip and behavior of the motherboard is the same as with it. It looks like it even can't get to bios. Strangely my EPROM reader detects error on pin 4 of Bios chip. I have ordered new SST29EE020 chip from China and we will see if it change something...