mkarcher wrote on 2024-07-16, 16:02:

You can add a x1 dirty tag RAM to the UM82C480 to get it into sensible write back mode. IIRC there is at least one VOGONs thread about that.

Interesting, but that's really beyond my soldering skills. One thing I noticed, with the FX3000, is that a 50 MHz 486DX will run a little bit faster with L2 cache disabled, provided the DRAM employed is capable of 0WS both read and write at that bus speed.

Anyway, back on topic... today a nice Soyo 019R1 arrived at my home. Now I'm doing some stability tests with a 486DLC then, in a few days, I will try with the RapidCAD chip. It seems it's as fast as the BC3486.

Just a quick update... new board, same old problems! Ok, I officially give up. Time to put the RapidCAD inside a display case and find something else to tinker with. 😀