Confused about UEFI backward compatibility

[brocks]

I'm about to get a new MB, but I want to make sure it's compatible with my OS and drives. It seems that all the boards I'm looking at come with a UEFI BIOS. I guess I want that, because it supports 3TB+ drives, but the Wikipedia article on UEFI says this:

"With the release of Windows 8 in October 2012, Microsoft's certification requirements now require that computers include firmware that implements the UEFI specification. Furthermore, if the computer supports the "Connected Standby" feature of Windows 8, then the firmware is not permitted to contain a Compatibility Support Module (CSM). As such, systems that support Connected Standby are incapable of booting Legacy BIOS operating systems."

I mostly use Windows 7, but I occasionally boot up XP to use my old printer and scanner that don't have 64 bit device drivers. I also have a lot (dozens) of old hard drives with MBRs, that have valuable data on them --- including all of my boot drives. So I'm very concerned with backward compatibility.

I've looked at several websites that review motherboards, as well as the places like Newegg that sell them, and I can't find anything about CSM or connected standby. Can someone tell me if there is a good source for that information? I'm leaning toward getting a Gigabyte Z87X-UD3H, if that helps.

Thank you.

 

[Ketchup]

If I understand your question, the answer is: don't use it. If you don't plan to use Windows 8 right now, you can just disable the UEFI (switch to Legacy) in the BIOS, and your computer should run XP and 7 just fine.

Another option (which I have chosen) is to continue my use of XP in a virtual environment (VMware). That way you can run 7 with the UEFI, and be ready to add future OS's without having to make a major system change.

 

[brocks]

If I understand your question, the answer is: don't use it. If you don't plan to use Windows 8 right now, you can just disable the UEFI (switch to Legacy) in the BIOS, and your computer should run XP and 7 just fine.

But if I understand the paragraph I quoted from Wikipedia, Microsoft has forbidden UEFI BIOSes to have that option if they support Connected Standby. So my question is, how can I know whether it has that option or not, before I order the MB?

 

[Ketchup]

So you want to use Connected Standby but not UEFI?

 

[brocks]

So you want to use Connected Standby but not UEFI?

No, I want a UEFI BIOS that does NOT support Connected Standby, so it has the option to revert to the old-style BIOS.

 

[Ketchup]

I suggest you look at the motherboard manual here:

http://download.gigabyte.us/FileList/Manual/mb_manual_ga-z87x-ud3h_e.pdf

Pages 51 through 53 seem to discuss the information you are looking for. As with all other boards, you will have the option to use, or not to use, UEFI.

 

[brocks]

I suggest you look at the motherboard manual here:

http://download.gigabyte.us/FileList/Manual/mb_manual_ga-z87x-ud3h_e.pdf

Pages 51 through 53 seem to discuss the information you are looking for. As with all other boards, you will have the option to use, or not to use, UEFI.

Thank you so much! It shows this option:

" UEFI and Legacy -- Allows booting from operating systems that support legacy option ROM or UEFI option ROM. "

I tried looking at the gigabyte website earlier, but it froze on me. It must have been either a temporary glitch, or something on my end. But your link worked perfectly.

Thanks again for the help.

 

[Ketchup]

Glad that cleared it up. Sorry it took me a few posts to get what you were asking. After this generation though, at least in my mind, the availability of that "legacy" option will be somewhat of a mystery.

 

[vailr]

The Compatibility Support Module (CSM) feature has an enable/disable option in bios setup. Default setting is enabled.
In order to run completely in UEFI mode, the video card bios must include a "UEFI GOP compatible bios", which may require flash modding the video card bios with a compatible firmware. Also requires that Windows 8 be installed fresh in true UEFI mode.
Discussion about this for MSI branded video cards here:
http://forum-en.msi.com/index.php?topic=167763.0
Note: the bios restriction you quoted:
"if the computer supports the "Connected Standby" feature of Windows 8, then the firmware is not permitted to contain a Compatibility Support Module (CSM)."
would simply necessitate disabling CSM in bios setup.

A Gigabyte Z77X-UD5H board's bios setup screen that shows the CSM option:

 

[brocks]

Vailr, thanks for the info, but I think I'm going to try going without a video card this time around. From what I've read, the Intel 4600 graphics built into the latest CPUs are good enough for me, since I don't do any serious gaming.

 

[vailr]

@brocks: The Z87 motherboard's bios should already contain the required "Intel UEFI GOP compatible bios".
See "Intel GOPdriver":
http://forums.tweaktown.com/gigabyte/48085-gigabyte-modified-bios-54.html#post465375

So, with an Z87 board, a "true UEFI" mode installation of Windows 8/8.1 would allow for speedier boot times, if that was something you were interested in.