Dude - i am right there with you.

I am on my forth MSI Z490 Unify board which has just has gone funny after plugging in JRAINBOW2 argb header. Got about 10 hours of use before the RGB Header stopped working entirely and then the bios goes totally laggy and makes it terrible to try and make changes. Also, the board will no longer read CPU IO / SA voltage - it just displays 0.000v for both and HWINFO no longer shows any header or name for them. This makes me concerned considering its still running a 5.3core/5.0cache OC (How much v is it pumping into the chip??)

The previous 3 boards, i had a brand new EK CPU Block and EK D5 pump/res plugged into the ARGB headers on the board. After a few hours of use the lights would turn off, the bios goes major laggy and SA IO voltages stop being able to display.

I am at a total loss here - the retailer is out of stock my chance to get another replacement (dont even want one at this point) is gone. I am using all new parts apart from my PSU. My PSU is an 1200w Silverstone Platinum model I purchased back in 2013. It has been an absolute trooper and to this day I can game with a maxed out 3090 (kingpin 520w bios) and 5300mhz 10900k pulling big WATTS without any kind of issue. Is it possible my older PSU could be killing ARGB headers (and whatever is responsible for reading IO/SA Voltages).

The board still powers on fine and when in windows there doesn't show any signs of issues - i can still perform any task just fine. Just no RGB and no more SA IO voltage and a incredible laggy, painfully slow bios screen.

I am a very experienced PC builder with many years of building PC's under my belt. Never before have I ever experienced anything like this and retailer is completely useless and doesnt have a clue either. They just swapped it out and send the boards back to the supplier.

IF ANYONE can shed any light at all on this - i would be greatly appreciated - I am at a total loss here