On Fri, 13 May 2022 at 19:59, Phil Thane phil@pthane.co.uk wrote:

Memtest isn't installed and isn't available from Ubuntu repositories. probably could get it from elsewhere but chances are I just crash/hang the thing again!

Memtest is supposed to be booted off a usb drive or a cd. You can get it from https://www.memtest.org/archives and get version 5.31, follow the instructions to write that to a bootable media and then test the ram.

Secondary computer you could use?

Kubuntu system monitor shows 4GB but no error messages, and trying to run it just hung the PC again so doing this from a different machine.

Nothing in the kernel logs? dmesg? No exotic PCI cards in the system or other experimental drivers loaded?

uname -a shows kernel version 5.15.x.x and AMD X86-64

Can't see anything in UEFI to suggest setting problem. It shows 8GB installed and 8GB available.

Suggests your linux install is messed up? Can you reinstall or re-download the ISO again, verify that the ISO is not corrupted and burn another install disk and try re-installing?

On 13/05/2022 19:41, Srdjan Todorovic wrote:

...

On Fri, 13 May 2022 at 19:30, Phil Thane phil@pthane.co.uk wrote:

...

It's now very unstable given to hanging whenever asked to do anything like move/close a window, so hope I get to the end of this without a problem.

What does Memtest86 say about your ram? This should be the very first thing you do.

...

I *think* there might be a problem with RAM and/or mainboard RAM slots. There are 2x4GB modules fitted. (Crucial Ballistix not cheapo stuff). UEFI setup and lshw both report 8GB but free only shows 4GB. That was the case under Mint, and still is with a fresh install of Kubuntu.

Which version of Kubuntu? What kernel version and architecture? uname -a

Are you sure your kernel is not 32bit without PAE extensions? That would limit to 4GB usable RAM even if you had more. Any weird BIOS / UEFI settings that might put it into some sort of legacy mode to only give you 4GB?

...

Any suggestions before I lash out on new RAM? Because if I do it's pretty much guaranteed to be something else. Or do any of you have old DDR 3 you've replaced with bigger sticks and not got around to selling on Ebay? Cheap preferred but no reasonable price refused!

I have 2 sticks of 4GB each, DDR3 ECC server ram - not sure if it would work (you would need to check if your CPU + motherboard could support it), but might be open to taking £10 or something + postage? I would need to do Memtest86 on that ram to make sure it's ok.

Thanks, Srdjan