So I recently stopped using the original release BIOS from 2011 for my RIVE and now I lose one of my sticks of ram every time I try to run 5Ghz regardless of voltage ram voltage/timings/frequency. I boot up the BIOS see all 4 sticks and once I'm in windows and check Task manager I'm at 12GB. Once I reboot to BIOS, my A channel stick has it's frequency set to 1600 and timings to 10-10-10-28 but still doesn't get recognized in windows.

Anyone know what could be the cause before I start searching for a different BIOS or switch back to the initial release one?

Sounds like there's more variables to check. If this has only started happening after changing the BIOS, then it's possible that the default value for a particular voltage or timing is causing instability.

It might be a RIVE thing cause I have a black edition and a normal RIVE and they both drop mem channels and reset timings like crazy.

My asrock Extreme 11 did the same(for me it was D chanel), cleaning the socket wth some contact cleaner did the job

Otherwise try bone stock settings and see if it returns, some boards loose mem channels, but usually that's because of high BCLK, which surely isn't the issue with R4E...