Hello everyone, My X58 FTW3 has been running forever with an I7 920 without issues. 2 Days ago I swapped out the I7 for a Xeon W3690. It booted right up into Linux and Windows 7. While in Windows 7, I noticed that it was only running at 2.66 GHz. It is recognized as a Xeon W3690 with all cores recognized and hyper threading working.
I rebooted into the BIOS and found out that the multiplier is set at 20X. In the BIOS the field to change the multiplier is not accessible. I cannot for the life of me figure out how to set it to 26X. That is what the Xeon is supposed to be running at.
I thought maybe there is a problem with the CPU, so I downloaded and ran the Intel processor diagnostic tool. All went well until it got to the part of the test that tests the frequency. It failed right away! That told me that it is indeed running at 133X20=2.66 and not 133X26=3.46.
So my question is how set the multiplier to 26X where it should be for the W3690 CPU.
 

Are you sure it's a 3690? They are unlocked and stock is like 3.5 GHz or so. Since I'm sure you got a used one it could be either a different CPU or bad

Is the BIOS up to date with the latest version?
I would unplug the PSu from the wall, remove the battery, hit the start button to release any stored electric.
Press the clear CMOS button for 30 seconds.
Put the battery back in, plug in the PSU, start the computer and go in the BIOS and put it back to optimized settings, hit F10, save and exit, it will reboot.
Go back into the BIOS and see how it is, set time. Make sure to check the hard drive setting if changes for a SSD
 

Just a reminder, use the i7 when updating the bios. Using a cpu thats not/half recognized right will most certainly give you a headache over time 🤪