Reply 60 of 70, by havli
enaiel wrote on 2022-04-02, 01:27:
We're able to actually communicate with the PLL now and get back the FSB, so that's much better. Made some minor changes to the last few bytes we're sending based on default values from the datasheet. If that doesn't work, then I'm officially out of ideas as everything looks exactly like in the datasheet.
Please try to set the FSB to 130 first, and if that works, then try 111.
Thanks for testing!
Tried the version 0.2.0 and unfortunately not much luck. This time there are not artifacts, just good old freeze 😁 when trying to set the new FSB value. Tried the 130 MHz as you suggested. Well, I guess we can just leave it. The range of available FSB would be pretty limited anyway (originally I hoped for 66 MHz, so CPU az 266 MHz)... which is not possible. And there are other ways of reducing the speed if needed.
Btw - before I started testing, I was able to reach around 1GB/s memory copy bandwidth in Aida64. Now it maxes out at 700 or so MB/s. Perhaps some bit changed by accident in the cmos memory that alters memory settings? Many restarts and shutdows cycles didn't help. Not evel loading optimized defaults in BIOS. I will open the case and do clear cmos, that should definitely restore factory settings and the corect bandwidth.
Not that it matters anyway (for DOS gaming), but it bugs me that I remember the performance used to be better and now I can't reach it again. 😁
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