Hello everyone,

I've got a PC Chips/Gain Tech M912 [0] for my 486 setup which allowed me to put a DX4ODRO100. As we know this overdrive cpu doesn't require an overdrive socket as it comes with a voltage regulator for 3.3V voltage.

Although, the mobo has native 5V or 3.3V support and it's also marked compatible to DX4 on the silk screen.

The issue is the 3.3V is totally rippled and in an extra caring effort I would like to get it back to clean.

Now I can spot only one TO220 transistor which has also a minimal heatsink which makes me think it's the one doing the voltage regulating. It's also have 1% resistors very close to it, which really makes me think it's the one. I can't spot any leaking caps, and the system is totally fine and stable by setting the mobo to 5V and let the ODPR do the work with it's regulator.

What's anyone experience on this? Does the ripple typically get cascaded from the PSU or it's due to the regulation into the motherboard most of the times? Is there a circuit reference for the regulation part - like, this was the de-facto standard back in the days?

Thanks to anyone who are keen to help.

[0] https://theretroweb.com/motherboards/s/pcchips-m912-v1.4-486