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Can't Disable CSM on My Rampage V Extreme

mouyahama
Level 7
Hi,
I was trying to disable Compatibility Support Module (CSM) on the UEFI as I heard it will decrease boot time but when I do that my SSD, HDD and NVMe drives disappears from the boot menu and when ever I start the PC I just be redirected to the UEFI again.

my build:
Intel Core i7-5820K
Asus Rampage V Extreme running BIOS Version 3402
32GB Kingston HyperX
NVIDIA GeForce GTX 1080 FE
HX1200i 80+ Platinum PSU
H100i V2
NVMe Samsung SSD 950 (476 GB) (primary boot drive)
Samsung SSD 850 PRO 1TB
WD Blue 4TB (3726 GB)
Microsoft Windows 10 Pro
7,820 Views
9 REPLIES 9

JustinThyme
Level 13
You cant install with CSM enabled then disable it after. Most M2s cant be used as a boot device with CSM enabled so Im surprised you even got it to work in the first place. The drives are still there and detected, just no UEFI boot partition is present so it cant find it. This takes up about 400MB and has its own partition. No partition, no UEFI boot. AFAIK you cant just change it. Takes a reinstall of the OS in UEFI configuration.



“Two things are infinite: the universe and human stupidity, I'm not sure about the former” ~ Albert Einstein

JustinThyme wrote:
You cant install with CSM enabled then disable it after. Most M2s cant be used as a boot device with CSM enabled so Im surprised you even got it to work in the first place. The drives are still there and detected, just no UEFI boot partition is present so it cant find it. This takes up about 400MB and has its own partition. No partition, no UEFI boot. AFAIK you cant just change it. Takes a reinstall of the OS in UEFI configuration.


so do you suggest reinstalling the windows 10 with CSM disabled because i have installed it with BIOS defaults which means CSM enabled with the sub options set all to legacy only.

JustinThyme wrote:
You cant install with CSM enabled then disable it after. Most M2s cant be used as a boot device with CSM enabled so Im surprised you even got it to work in the first place. The drives are still there and detected, just no UEFI boot partition is present so it cant find it. This takes up about 400MB and has its own partition. No partition, no UEFI boot. AFAIK you cant just change it. Takes a reinstall of the OS in UEFI configuration.


thanks for the advice but do you think I can switch CSM off safely and get the UEFI to detect all my drives when I switch windows 10 Installation from Legacy to UEFI Without reinstalling it using gdisk utility?

JustinThyme
Level 13
Its not that your drives are not being detected. Go into your PCH controller or main menu in the BIOS and unless they are dead you will see them there. What you are not seeing fromt he boot menu is a boot partition. I have multiple drives installed and my BIOS sees only one bootable source because I have secure boot enabled and CSM disabled. No UEFI, no boot.



“Two things are infinite: the universe and human stupidity, I'm not sure about the former” ~ Albert Einstein

Brighttail
Level 11
The R5E10 installed just fine on a 950 pro with CSM on. Not sure if that will effect boot times or anything but no problems with the install.

I have two SM961s as game drives in RAID, so I don't think turning CSM off at this point or even reinstalling is going to help speed up boot times any. If I turned CSM off would the system recognize the 961s as a drive using windows RAID?
Panteks Enthoo Elite / Asus x299 Rampage VI Extreme / Intel I9-7900X / Corsair Dominator RGB 3200MHz

MSI GTX 1080 TI / 2x Intel 900p / Samsung 970 Pro 512GB

Samsung 850 PRO 512GB / Western Digital Gold 8TB HD

Corsair AX 1200i / Corsair Platinum K95 / Asus Chakram

Acer XB321HK 4k, IPS, G-sync Monitor / Water Cooled / Asus G571JT Laptop

Brighttail wrote:
The R5E10 installed just fine on a 950 pro with CSM on. Not sure if that will effect boot times or anything but no problems with the install.

I have two SM961s as game drives in RAID, so I don't think turning CSM off at this point or even reinstalling is going to help speed up boot times any. If I turned CSM off would the system recognize the 961s as a drive using windows RAID?


I could not get the OS to install on a 950 pro with CSM enabled.

I dont think it has anything to do with boot times. Its secure boot with a digital foot print.

This explains some of it without retyping info that is already available.

http://www.howtogeek.com/175649/what-you-need-to-know-about-using-uefi-instead-of-the-bios/



“Two things are infinite: the universe and human stupidity, I'm not sure about the former” ~ Albert Einstein

Zarathustraa
Level 7
You can use the gparted live cd to make sure you have gpt setup, and not an mbr partition table

Chino
Level 15

Chino wrote:
If you want to disable CSM, it must be done before you install your OS.


I understand this, Chino. My question tho was, "If I can already install my OS on an NVME drive with it on, does it really make any difference whether it is on or off? (for boot times or any other reasons) Also If i install with it off, can i still RAID my other two SM961 as a games drive using Windows RAID?"

Just curious if i'd get better performance with it off as I'm already using the UEFI install with it currently on.
Panteks Enthoo Elite / Asus x299 Rampage VI Extreme / Intel I9-7900X / Corsair Dominator RGB 3200MHz

MSI GTX 1080 TI / 2x Intel 900p / Samsung 970 Pro 512GB

Samsung 850 PRO 512GB / Western Digital Gold 8TB HD

Corsair AX 1200i / Corsair Platinum K95 / Asus Chakram

Acer XB321HK 4k, IPS, G-sync Monitor / Water Cooled / Asus G571JT Laptop