First post, by GigAHerZ
I've been reading this forum for few years and have accumulated few of computers for my own interest. Now it is time to register to this forum and join you guys. 😀
For the first topic i have a small problem with my 386 PC.
It's a Am386DX40 on a PC CHIPS based motherboard.
It had soldered 128KB of L2 cache. (instead of jumpers, there were also wires soldered) At the same time, it had holes and everything for another bank of cache chips and a separate write back cache chip.
Of course i desoldered the chips and soldered the sockets back instead, added the ceramic capacitors, replaced the wires with jumper pins etc.
While mostly all is good and well, there is one interesting problem. (And this problem was present before i attacked the MB with my soldering gun)
It's a bit unstable, when L2 cache is enabled. When emm386 is also loaded, there's an interesting artifact with norton commander as well: when command runs in command line, and then norton commander returns back, then 2 vertical rows of characters, that are not filled with filenames, but are empty, are left unupdated and contain the letters from the background command line printout.
I've tried numerous different tools to try to reliably diagnose the issue, but nothing seems to be picking up the failure. I've resoldered the sockets and reseated & replaced the chips maybe dozen times already but still no luck. The closest thing i've got is that maybe 1/20 times, when i run doom2 benchmark, from one point onwards, it kind of misses correct steps and starts to shoot to slightly wrong directions. But 1/20 chance to even get that result is not good enough for diagnosis tool.
So i'm coming to you. Do you know any tools to try out for testing L2 cache? Even better, if it would print out faulty addresses so i could find proper chip and traces to it on the board as well.
Many thanks already to all the community. You can't even imangine how much information i have already read from here and used for my entertainment with retro pcs. Thank you!
"640K ought to be enough for anybody." - And i intend to get every last bit out of it even after loading every damn driver!