Cuda 8.0 RC fails to install on Ubuntu 16.04 LTS with gcc 5.4.0

Just added titan X pascal to existing titan X Maxwell. Updated Ubuntu from 14.04 to 16.04 and trying to install 8.0 RC and have the following issue. Would appreciate any help.

Leopard-WS:~$ sudo dpkg -i Downloads/cuda-repo-ubuntu1604-8-0-rc_8.0.27-1_amd64.deb
(Reading database … 271555 files and directories currently installed.)
Preparing to unpack …/cuda-repo-ubuntu1604-8-0-rc_8.0.27-1_amd64.deb …
Unpacking cuda-repo-ubuntu1604-8-0-rc (8.0.27-1) over (8.0.27-1) …
Setting up cuda-repo-ubuntu1604-8-0-rc (8.0.27-1) …

Leopard-WS:~$ sudo apt-get update
Get:1 file:/var/cuda-repo-8-0-rc InRelease
Ign:1 file:/var/cuda-repo-8-0-rc InRelease
Get:2 file:/var/cuda-repo-8-0-rc Release [574 B]
Get:2 file:/var/cuda-repo-8-0-rc Release [574 B]
Hit:4 xenial InRelease
Hit:5 xenial-updates InRelease
Hit:6 xenial-backports InRelease
Hit:7 xenial InRelease
Hit:8 xenial-security InRelease
Reading package lists… Done
W: file:///var/cuda-repo-8-0-rc/Release.gpg: Signature by key 889BEE522DA690103C4B085ED88C3D385C37D3BE uses weak digest algorithm (SHA1)

Apparently, it’s a known issue and found the fix.

sudo sh --override

I have the same issue, but I don’t have any *.run file in /var/cuda-repo-8-0-rc, what should I do in this case?

You shouldn’t be using CUDA 8.0RC any more, switch to CUDA 8.0

If you are still having trouble, read the install guide and also the forum sticky post about the repository signing key change.

If still having trouble, try switching to the runfile install method. That is effectively what VG6 did above. You have to download the .run file.