The MCH is not longer located on the motherboard therefore the value is zero, that entry should not actually be on the system BIOS. That has been removed on the latest BIOS available.
The IDU still reporting the MCH temperature is a know issue of this version, you can confirm it on the following site:
Concerning the system not updating the system bios, you may try a BIOS recovery update instead of the express method. Also try clearing the system CMOS before attempting the update, by removing the CMOS battery and all power cables from the power supply to the motherboard, leaving the system without power for 20 minutes at least
1st: There is 3 different ways to update the BIOS for this Mother Board. Intel has a nice video on there web site on how this is done. Search Intel's site for your "DESKTOP BOARD" then look for your "BIOS UPDATE" INSTRUCTIONS can be found in the read me notes. Do not remove the BIOS jumper since this will cause BIOS settings to change from what you may have customized. Leave jumper on the normal position termials 1 and 2. Note don't update BIOS unless you know the problem is covered in the updated BIOS. See below.
2nd: (Your problem with the Memory Control Hub temp I don't have a answer for that since I have not ran across that problem) and have not needed to research it. I will suggest make sure you have Memory that has been approved for use with your mother board, and the latest chipset driver.
To identify your current BIOS version, check the BIOS version string:
During boot, enter the BIOS setup by pressing F2.
Check the Main menu.
The third segment of the BIOS Version (a 4-digit number) is the current BIOS version.
Press Escape to exit BIOS Setup.
Example BIOS ID string showing the version number:
Update the BIOS on your computer only if the newer BIOS version specifically solves a problem you have. We do not recommend BIOS updates for computers that do not need it. You can view all new BIOS fixes in the Release Notes included on the BIOS download page in Download Center.
Downgrading the BIOS to an earlier version is not recommended and may not be supported. An earlier BIOS version may not contain the support for the latest processors, bug fixes, critical security updates, or support the latest board revisions currently being manufactured.
Before initiating a BIOS update, be sure to read and precisely follow the update instructions. You may wish to print the instructions for easy reference.
If a BIOS update process is interrupted, your computer may not function properly. We recommend the process be done in an environment with a steady power supply (preferably with UPS).
All images in the examples used in the instructions are specific to certain desktop boards and are for illustration purposes only. You need to select the correct BIOS files for your desktop board.
There are up to six methods of updating an Intel® Desktop Board BIOS to the latest version. The number of options made available for any particular board may vary, depending on drive support and BIOS update file size. You only need to use one.
All BIOS update files for Intel® Desktop Boards are available on Intel's
Refer to this matrix to see which update method will work for you.
1The Express BIOS Update is the simplest and most common method of updating a BIOS.
2 The F7 BIOS Flash Update is available on Intel® Desktop Boards beginning in 2009. To see if your board supports this feature, in BIOS Setup, check the Advanced > Boot Configuration menu for the setting Display F7 to Update BIOS.
3 The floppy disk methods may be used only when the BIOS update files are small enough to fit on a floppy disk (smaller than 1.44MB) and if the desktop board includes floppy drive support.