First post, by adalbert
I am trying to get dual Tualatin setup working (some details here Tualatin BIOS update for Tyan S1834D (Tiger 133)) with my Tyan S1834D motherboard, so I got two MS-6905 Master slotkets, but different revisions (VER: 2.3, VER: 2)
I successfully modded MS-6905 VER 2.3 (i made 3 holes larger and insulated them), it works with wire-modded Pentium III-S SL5XL 1.4GHz. I wanted to add a second CPU, so I performed the same mod with VER: 2 slotket.
It didn't work at all with P III-S 1.4GHz (SL6BY this time), so I un-did the mod and tested it with Coppermines. 733MHz (133MHz FSB) P3 didn't work. Then I set the jumpers on the slotket to 100MHz and it worked, detected as Pentium 550MHz. Pentium III 800MHz also worked at 100MHz. But I always got a black screen when FSB was set to 133MHz.
This is my working Pentium III-S SL5XL 1.4GHz with MS-6905 Master VER: 2.3 slotket (2-3 on JV0, JV2, 2-3 on J3 /this shouldn't be important here/, other jumpers are open):
When I set identical jumpers on VER: 2, it didn't work with Tualatin or Coppermine.
I also tried different jumper settings on VER: 2, auto voltage (1-2 on JV0,1,2,3,4) FSB 133 (J4 and J1 open). Tested with 733MHz P3. Didn't work.
These jumpers did work with 733MHz P3 and 800MHz P3, but they were in 100MHz FSB mode (1-2 on JV0,1,2,3,4; 2-3 on J4):
Any ideas what could be done to fix it? I only tested these CPUs in single slot, I didn't try running both Tualatins at once. Are there known differences between VER: 2 and VER: 2.3 that can be fixed so they will perform the same? I could take high-res photos of both but maybe someone already knows could be the problem.
EDIT: Ver: 2.3 has TVC16222A chip. VER: 2 has just TVC16222 chip. Could non-A version be unsuitable for 133MHz operation? I could buy new version and replace it. It is still being produced. But I don't know if it makes any sense.
Repair videos: https://youtu.be/T6mXM1tA7pA