Boot issues: M.2, UEFI, CSM Disabled

voodoodrul

Senior member
Jul 29, 2005
521
1
81
Howdy all

The Parts:
Asus Maximus VII Impact Motherboard
Kingston Predator 240gb M.2 drive (pulled from the HHHL adapter)

The settings:
Default BIOS settings except
CSM Disabled (full UEFI mode)
Secure Boot on
Fast Boot on or off

I'm having a heck of a time getting this build to reliably boot. It hangs just after the boot splash when the usual spinner for Win8 boot would appear. I can install Windows 8 - I used this (http://windows.microsoft.com/en-us/windows-8/create-reset-refresh-media) to create the UEFI boot media. The problems seem to occur about 50% of the time on reboots after the initial install. I can almost guarantee a boot hang if I successfully boot into Windows, put the machine to sleep, wake it, then reboot. Generally I have to power cycle the machine and it may or may not work after that. The "Fast Boot" option seems to have no effect. With CSM enabled, things tend to be more reliable. I'm guessing the root cause has to do with Secure Boot.

FWIW, I had exactly the same behavior on another build, the only consistent factor being the M.2 drive being used. In the other machine, the M.2 was seated in a PCIe adapter card, but the behavior was the same.

Any suggestions?
 

Burpo

Diamond Member
Sep 10, 2013
4,223
473
126
Does your boot screen look like this?
boot-from-storage-devices.png


Boot_Menu.jpg
 

voodoodrul

Senior member
Jul 29, 2005
521
1
81
Burpo - no, I'm running CSM disabled. UEFI mode with CSM enabled is a legacy setting. So for me "Launch CSM" is disabled and all options under it go away.

Vailr - thanks for the handy guide. I'll definitely check it out.

Strange enough, if I plug in a crappy keyboard instead of my Corsair k70, it seems to boot reliably. Hmm.
 

Burpo

Diamond Member
Sep 10, 2013
4,223
473
126
Aha! The plot thickens..

http://forum.corsair.com/v2/showthread.php?p=763310

http://forum.corsair.com/v3/showthread.php?t=137940

work around..
" This issue is actually related to how certain BIOS in a small group of motherboards have a difficult time communicating with the keyboard in POST. To be frank, the USB enumeration from the keyboard is too quick for some BIOS to properly receive and hence ends up hanging the BIOS for a prolonged (2-3 mins) at a time. This doesn’t affect all BIOS either but it is aggravating for those who experience it. The temporary workaround you can use is to toggle the button on top of the keyboard to change the polling rate from 1/2/4/8 to BIOS and then change it back afterwards."
 
Last edited:

voodoodrul

Senior member
Jul 29, 2005
521
1
81
Thanks Burpo, spot on! At least that pinpoints the issue.

I am starting to question my love for this keyboard and their headset. Corsair makes decent RAM but everything else seems to be awesome on the surface yet have some show stopper issue. If your average $12 keyboard at Walmart can actually do the job, and a $120 keyboard can't, well wtf?