Update 8/25/2012 - I have got down to the root of the problem, and it's not good. I have been using this board since May, and have RMAd 4 different sets of RAM, all of which were used at their stock settings or even slower. I suspect this is indeed due to the board over-volting the memory due to a bug in the BIOS settings that leads to incorrect memory VRM settings.
Here's what I now know for sure:
The measurements shown in Intel Desktop Utility and in system setup > Fan Control & Real-Time Monitoring > Memory Voltage are correct. The measured voltages may differ from the settings, but the measurement is correct. I confirmed this by reading the voltage off the caps adjacent to the memory slots. If IDU reports 1.75v, I read 1.75 off that pad. If it reads 1.53v, I can read it off the caps. (Thanks go to erc, Daniel, David, and others in the tread for noticing this inconsistency)
This sequence can cause the motherboard to supply an incorrect voltage to the memory every time. Here's a video showing the sequence: https://skydrive.live.com/redir?resid=1AC889188B918540!569&authkey=!ADhaCNCCUVXtLTI
- Get the system to a clean state by resetting BIOS defaults
- Exit, let system warm boot, and go back into BIOS. Check voltage at Fan Control... - it will be correct (1.5 in my case) - video 0:00 to 0:30
- You can reboot multiple times here, or go into Windows, run IDU, and it will continue returning the correct voltage.
- Here's the problem: Now go to Performance, and change the value to Yes so you can see the memory/cpu settings. Don't change anything. Notice - the voltage setting will be correct here (1.5v in my case) - video 0:30 to 0:48
- Reboot. Go back into BIOS, and go to Fan Control... At this point, the voltage will be wrong. In the video attached, it shows 1.75v. - video 0:48 to 1:00
Now you're on track to kill the memory in a few days to a few months. Here's how to get back to defaults. - video 1:02 to 1:50
- Reset BIOS back to defaults, save settings, then TURN THE SYSTEM OFF. If you don't turn the system off, the buggy settings WILL PERSIST.
- Turn it back on, go into BIOS. Confirm voltage - it will be back to the correct default. - video 1:50
- Change your other settings back as needed for boot device, etc
- Boot up Windows, run IDU - voltage will be correct
At this time, I'm not worrying about timings, etc until this voltage issue is resolved. I'll update the thread once Intel is able to fix this firmware issue and work towards getting back to the 1600mhz my CPU and memory were designed for.
I have tried 3 different sets of memory trying to get to DDR3 1600mhz timings at 1.5v. Each time, in the BIOS, Performance, Memory - it shows that its automatically choosing 1.5v, 1333 MHz, timings 9-9-9-24. If I change from "Auto" to "XMP" profile setting, then it will show:
1600mhz, 1.8v, and the correct CAS/RAS timings.
My CPU (Intel Core i5-3550) could be damaged by voltages that high, so I have not attempted these settings.
I checked the memory's SPD data in CPU-Z, and it correctly shows the XMP profile for my Corsair XMS3 memory to be 1600mhz, 11-12-12-32, 1.5v.
I also attempted to use Crucial Ballistix Sport (1600 9-9-9-24 1.5v), and Mushkin Blackline (1600 10-10-10-24 1.5v) modules - all led to the same incorrect 1.8v XMP profile.
Can someone confirm if this is just a display bug, or if it will actually attempt to use 1.8v in the XMP profile? I would like to run my memory at max speed.