Hi
I have a couple if 486 33 and 66's, all of which over cooked 1 pin on 2 motherboards. 486's at 25/50 work fine. how can i test the 66's without risking my new motherboard? its pin D3. is it the cpu or motherboard doing this? could the cpus all be shorted on 1 pin?
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Are they 3.3v or 5v cpus? D3 is just a data pin, and that's whether it's socket 1,2, or 3.
I would say it's a motherboard issue.
You could measure the pin to gnd with a multimeter, either connected in the socket or not.
This is a very weird problem to have, maybe attach a photo?
Atari 2600, TI994a, Vic20, c64, ZX Spectrum 128, Amstrad CPC464, Atari 65XE, Commodore Plus/4, Amiga 500
PC's from XT 8088, 486, Pentium MMX, K6, Athlon, P3, P4, 775, to current Ryzen 5600x.
pics. 0 ohms to ground. i followed the manual for jumpers.
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That's C5 on the socket, which is VSS (GND).
Maybe a cpu has been plugged in the wrong orientation?
i just checked, so if the cpu was plugged in 180 degrees then that would be VCC going directly into the GND pin on the motherboard.
90 degrees either way is A29 (Address pin) or BS8# which is an active low signal.
Atari 2600, TI994a, Vic20, c64, ZX Spectrum 128, Amstrad CPC464, Atari 65XE, Commodore Plus/4, Amiga 500
PC's from XT 8088, 486, Pentium MMX, K6, Athlon, P3, P4, 775, to current Ryzen 5600x.
humm. pretty sure i had dot to top right of pics.
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