Do you have a Trident ISA video and an S3 Virge installed? Just stick in whatever one of a PCI or AGP card you know works. If AGP, make sure it is fully inserted.

Clear the CMOS and put back in the CMOS battery, if it can hold settings. Or buy a new coin cell.

Try a different power supply.

Also read the manual in the troubleshooting section:
https://ia802509.us.archive.org/view_archive. … Fm5emapro10.pdf

the3dfxdude wrote on 2023-01-10, 18:03:

Do you have a Trident ISA video and an S3 Virge installed? Just stick in whatever one of a PCI or AGP card you know works. If AG […]
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Do you have a Trident ISA video and an S3 Virge installed? Just stick in whatever one of a PCI or AGP card you know works. If AGP, make sure it is fully inserted.

Clear the CMOS and put back in the CMOS battery, if it can hold settings. Or buy a new coin cell.

Try a different power supply.

Also read the manual in the troubleshooting section:
https://ia802509.us.archive.org/view_archive. … Fm5emapro10.pdf

Thanks for your help.

The only graphics card installed is the Trident ISA. I'll put the CMOS battery back in a clear the CMOS using the jumper setting but I can't imagine that doing much since the battery has been removed.

Why did you suggest using a different power supply?

I've swapped the memory out for 2 x 64mb EDO Dimms but that hasn't solved the problem. I've also tried a different CPU and removed the motherboard from it's case in case there was a short somewhere.

I'm thinking perhaps the USB to PS2 has fried something, is that a possibility?

cookertron wrote on 2023-01-10, 18:30:

Why did you suggest using a different power supply?

Because power supplies can go marginal and start introducing instability, or poor behavior at boot. This can happen gradually depending on use. But, I think the cmos should be reset and battery installed. So I don't know what parts you have on hand, but since you have already brought the computer down to minimum configuration from what I can tell and checked memory and cpu. Now is left to do the remaining process of elimination. The power supply is going to be the next to try to eliminate. Of course caps on the mother board can go marginal too, but you'd have to do an inspection to know or swap in a similar board to check if everything else is ok. I doubt there is a short because the system must be getting a power good from the power supply, but there again, we need to check the power supply to be sure it's really ok.

cookertron wrote:

I'm thinking perhaps the USB to PS2 has fried something, is that a possibility?

I've not heard of that. I'm guessing you weren't originally using this either? Do you have all the parts back in that were originally working for you?

the3dfxdude wrote on 2023-01-11, 00:29:

Because power supplies can go marginal and start introducing instability, or poor behavior at boot. This can happen gradually depending on use. But, I think the cmos should be reset and battery installed. So I don't know what parts you have on hand, but since you have already brought the computer down to minimum configuration from what I can tell and checked memory and cpu. Now is left to do the remaining process of elimination. The power supply is going to be the next to try to eliminate. Of course caps on the mother board can go marginal too, but you'd have to do an inspection to know or swap in a similar board to check if everything else is ok. I doubt there is a short because the system must be getting a power good from the power supply, but there again, we need to check the power supply to be sure it's really ok.

I've not heard of that. I'm guessing you weren't originally using this either? Do you have all the parts back in that were originally working for you?

The power supply has been changed but the problem persists. It was the first time I'd used the USB to PS2 adapter. I will say this, if I plug in a USB keyboard and press a key the system stops altogether.

Sigh, this is very frustrating!

Wow that is super slow.... think my 286 boots quicker...
Sounds like something happened with that USB to PS2 adapter. It is possible that it messed up something in the Southbridge.....
Curious why you used an adapter when the board has both USB and PS2 ports (according to https://theretroweb.com/motherboards/s/soyo-sy-5ema) ?

Horun wrote on 2023-01-11, 02:39:

Curious why you used an adapter when the board has both USB and PS2 ports (according to https://theretroweb.com/motherboards/s/soyo-sy-5ema) ?

Because I have a PS2 mouse and a USB keyboard and didn't like the idea of them not matching.

I think I'm going to have to go blown capacitor hunting. Not ideal as my soldering skills are terrible 😔