Hi everyone guys
I am PC @ live and I collect PCs and CPUs.
I have various PCs from 286 up to Core2 Duo, including an AST Bravo MS Pro (P.Pro 200MHz / 256KB), many SKT7 (K6-MII-Pentium-K5-C6), 2 Pentium 3 1400, a P4 423 2GHz RDRAM , etc ...
I also have various 486s, a 486DLC 40, a 386 40, and a 286 LPX 16MHz with TACT chipset and 10MHz coprocessor.
As a hobby I repair my PSUs, and repaired several MBs by changing the electrolytic capacitors.
I have several MBs to repair in my spare time, for now I'm concentrating on a Siemens D1120 SKT370.
The MB has 4slot PCI and integrated Audio, NB intel 810 FW82810 chipset and SB intel FW82801AA, Gen.Clock W147GH and a UCC3588D
The BIOS is Phoenix Version 4.06 Rev 1.07.1120
The CPU is a Celeron 566MHz.
The MB worked but suddenly it didn't start at startup. 😠
I made the following checks:
CMOS battery Measured voltage 3.03V then OK.
POST card inserted at display start stopped on -- --
LEDs on -12V + 12V + 5V + 3.3V CLK and RESET
Perhaps the RESET LED should light up by pressing the button, but here it is strangely? on (fixed)
Voltage measurements on mosfets and coils:
76129S Pin1 3.84V Pin2 5.09V Pin3 1.56V
76129S (near large coil) Pin1 0.00V Pin2 1.55V Pin3 0.02V
Large coil 1.53V
Small coil 5.09V
EZ1085CM (near CPU) Pin1 0.27V Pin2 1.52V Pin3 3.32V
EZ1085CM (near RAM) Pin1 0.59V Pin2 1.85V Pin3 3.32V
L495702.5 Pin1 4.79V Pin2 0.89V Pin3 3.38V
ST CHN K011 78M05 Pin1 12.20V Pin2 0.02V Pin3 5.10V

Tried to start without RAM and also without CPU, but no Beep, but I'll have to try again by connecting an external speaker, I don't know if the integrated one works ???

I look forward to suggestions and I can post some images.
Thank you