First post, by polishvito
Wondering if anyone can help me with this one:
Working on my IBM 5150 (Rev B). I got this AST Six Pak Plus in a box of random parts and I wanted to try using it for this machine. Unfortunately when this card is placed in the machine, it won't post. The power supply, hard drive still power on/spin up so the power supply is not going into protection mode. I've tried in multiple slots (and can verify other cards work in those slots). I removed all the ram, ran them through a tester (only one bad chip surprisingly), deoxit in all sockets, cleaned connector etc. I've verified that the switch settings are correct on the card and on my 5150 (256k on the motherboard), but even if it was a matter of bad switch settings or bad ram, I don't understand why the machine would not even post.
I have a different ram card that adds 256k and when that is in the 5150 it works fine. I want my 640k though!!
I also disabled the serial/parallel ports by removing the jumpers on the card, and even with no other cards in the machine, it still won't post