Think this manual might be closer, forgot to add it a minute ago.

i would start with the mmx and the multi at 3x. when it boots at 200mhz you atleast know you can alter the settings correctly. then try it at the settings you need for the winchip. When the intel boots try the winchip (or cyrix).

Remember: the intel uses 2.8v and the other cpu's might need a higher voltage to work correctly (info is on the chip).

If you can't get the chips to work it might be that the bios doesn't support them ( but usually the bios will show the wrong speed but machine will work correctly).

Cyrix and winchip have bad fpu performance and are much slower compared to the intel when used in games. The mmx is a very nice chip and only a (much) higher clocked amd is better.

Edit: the cyrix should be set to a lower speed: 166+ is probably a real 133mhz cpu. You could also set it lower (2x60mhz for example) and start from there. it will probably not work at 166mhz AND needs a good cooler!
Edit 2: To get the intel more stable, try different psu, different ram, better cpu cooling/paste, run it at 200mhz or bump the voltage to 2.9v, check caps on board for leaks.

also: the chipset can cache up to 512mb but only with 2mb cache. if the board has 512kb cache it will probably not cache beyond 64mb (maybe 128mb?) and will get a lot slower if you run it with more... Most intel boards did only cache 64mb ram and it is enough for win98se and the games that these systems can run.

Thanks, my main problem is that the manuals don't match the sticker on the board or the layout of stuff, the sticker does not have all the data for the dip switches, for example sw4 & 7 arent documented on the sticker. Sw5 isn't in the manuals at all that i can see. It's all a bit of a trial! 🤣

i would go with the stickers, as they came with the board. Not documented switches are probably reserved or do nothing so just leave them to ''off''.

Should be easy to setup the board:

3,5x 66mhz gives you the intel 233mmx, with 2.8v (setting at 1,5x is with intel the same and still works as 3,5x with this chip)
3x66mhz gives you the winchip 200mhz, probably 3.5v but there are versions that use 2.9v so do check
2x66mhz gives you the 133mhz cyrix 166+, this one has also 2 versions, 2.9v and 3.5v so check on the cpu

also run the board with one type of ram, so either sdram or edo but not both.

old cpu's can be broken so if both chips don''t work....

EDIT: looked at the manuals you posted and both do not have the sw1 switches like your board has it (you have it in a single place). in the manual all SW's are spread over the board so these are not the right manuals. You have a different board. Can't find the right manual either.

Thanks for the replies, so I have tried the Cyrix and winchip again using the setting on the stickers:

Cyrix 166+ switch settings Sw1 on, sw2 on, sw3 on sw4 off, sw5 off,sw6 off, sw7 off, sw8 off, sw9 off, sw10 off.

winchip switch settings sw1 on, sw2 on, sw3 on, sw4off, sw5 off,sw6 on, sw7 off, sw8 off, sw9 off, sw10 off.

Neither work, nothing on screen at all. also tried with those two undocumented switches 4,7 in the on position, no change.
Both the Cyrix and winchip were sold as working from ebay, bought at same time as the board, sadly I don't have another skt7 board to test them in, but not looking good for either one I guess.
The seller had tested the board with a intel 233mmx, the above screen shot is his picture from the ebay auction, the switch settings he used were sw 3,4 on, all others off,so running the 233mmx at 3.2 volt(according to the stickers), and with the undocumented sw4 on, these are also the only settings for me also that are even fairly stable, if i drop the voltage down to 2.8v then i get emm386 errors and all sorts of instability. It runs well enough to have used phils utimate VGA benchmarks to test some PCI cards with sw3,4 on, but if you run it for long in crashes out. I have tried 2 different known good 32mb dimms(66mhz), I'm not mixing ram or using more than 32mb. only a single hard disk and CD rom are installed along with a clean install of DOS 6.22.

I wonder if the custom BIOS for the silverball arcade machine might be the root of the cause. As i said, it has no options when entering the BIOS apart from load defaults, or not, that it. So I am wondering if CPU support may have been removed from the bios apart from Intel? Even so I would expect the board to do at least something with the other chips even if it did not correctly identify them of run them correctly.
Here is a little I managed to dig up on the silverball BIOS, seems it originally ran with a Pentium 133mhz or AMD K5, assuming this is the same board.
http://www.championsnet.net/fedoc_dokumente/T … rball_V6_en.pdf

Thanks again for the help,
Chris

Are you sure you are setting it for dual voltage CPUs? The fact that the MMX only works when setting the voltage to a level close to its VIO is weird. Try removing the CPU and testing the voltage pins with a multimeter.

No, I'm not sure at all, only info I have is that sticker on the board. I can not seem to find a manual for the VER0 of this board. Of course the other problem is, I am working with a bunch of 20+ year old hardware that eBay sellers have said is fine,perhaps not the best place to start, but Skt 7 is hard to find here in the UK, even on ebay and this is all I have, to be honest I just wanted to re-create the old machine we had in those years, hence the Cyrix and winchip(that was the buget choice I made as I also had a Power PC Macintosh for the real work, I was a journalist at the time). I don't have a multimeter or the skills to use it to be fair, I'm begining to think that this is a project I should have not started, or at least with other parts, but as I say, these bits are very hard to source here. I think these parts would be far more suitable for someone who has more experience and knowledge than myself(or the bin!!!), shame as it was all looking so good, even found the same case and video card from the old machine we had. Perhaps I better stick to my PIII's and netburst systems! 🤣