Xubuntu 14.04 breaks my computer!

Ok, where do I start here? Every now and than I test out various lts versions of xfce desktop. Having decided to return back to Xubuntu 14.04 which ran wonderfully I am now stuck with an interesting bug. On an earlier release + kernel my hardware was detected as a such-and-such card, now detects as something completely different. This includes all other hardware! Every now and then the computer freezes and on reboot hangs!

The only way back in is to boot yet another linux usb live stick of another version of linux then rebooting with usb stick removed. Somehow a new kernel version seems to be misinterpreting my hardware (unless of course my hardware is failing!)

Here are two file comparisons using the terminal command, "lspci" (without quotes).

First is from Knoppix 7.4.2

knoppix@Microknoppix:~$ uname -r
3.16.3-64
knoppix@Microknoppix:~$ lspci
00:00.0 Host bridge: Intel Corporation ValleyView SSA-CUnit (rev 0c)
00:02.0 VGA compatible controller: Intel Corporation ValleyView Gen7 (rev 0c)
00:13.0 SATA controller: Intel Corporation ValleyView 6-Port SATA AHCI Controller (rev 0c)
00:1a.0 Encryption controller: Intel Corporation ValleyView SEC (rev 0c)
00:1b.0 Audio device: Intel Corporation ValleyView High Definition Audio Controller (rev 0c)
00:1c.0 PCI bridge: Intel Corporation ValleyView PCI Express Root Port (rev 0c)
00:1c.1 PCI bridge: Intel Corporation ValleyView PCI Express Root Port (rev 0c)
00:1c.3 PCI bridge: Intel Corporation ValleyView PCI Express Root Port (rev 0c)
00:1d.0 USB controller: Intel Corporation ValleyView USB Enhanced Host Controller (rev 0c)
00:1f.0 ISA bridge: Intel Corporation ValleyView Power Control Unit (rev 0c)
00:1f.3 SMBus: Intel Corporation ValleyView SMBus Controller (rev 0c)
02:00.0 Network controller: Realtek Semiconductor Co., Ltd. RTL8821AE 802.11ac PCIe Wireless Network Adapter
03:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. Device 5286 (rev 01)
03:00.2 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8101E/RTL8102E PCI Express Fast Ethernet controller (rev 06)
knoppix@Microknoppix:~$

here's the one from Xubuntu 14.04:


pj@pj-X551MA:~$ uname -r
4.2.0-27-generic
00:00.0 Host bridge: Intel Corporation Atom Processor Z36xxx/Z37xxx Series SoC Transaction Register (rev 0c)
00:02.0 VGA compatible controller: Intel Corporation Atom Processor Z36xxx/Z37xxx Series Graphics & Display (rev 0c)
00:13.0 SATA controller: Intel Corporation Atom Processor E3800 Series SATA AHCI Controller (rev 0c)
00:1a.0 Encryption controller: Intel Corporation Atom Processor Z36xxx/Z37xxx Series Trusted Execution Engine (rev 0c)
00:1b.0 Audio device: Intel Corporation Atom Processor Z36xxx/Z37xxx Series High Definition Audio Controller (rev 0c)
00:1c.0 PCI bridge: Intel Corporation Atom Processor E3800 Series PCI Express Root Port 1 (rev 0c)
00:1c.1 PCI bridge: Intel Corporation Atom Processor E3800 Series PCI Express Root Port 2 (rev 0c)
00:1c.3 PCI bridge: Intel Corporation Atom Processor E3800 Series PCI Express Root Port 4 (rev 0c)
00:1d.0 USB controller: Intel Corporation Atom Processor Z36xxx/Z37xxx Series USB EHCI (rev 0c)
00:1f.0 ISA bridge: Intel Corporation Atom Processor Z36xxx/Z37xxx Series Power Control Unit (rev 0c)
00:1f.3 SMBus: Intel Corporation Atom Processor E3800 Series SMBus Controller (rev 0c)
02:00.0 Network controller: Realtek Semiconductor Co., Ltd. RTL8821AE 802.11ac PCIe Wireless Network Adapter
03:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTS5286 PCI Express Card Reader (rev 01)
03:00.2 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8101/2/6E PCI Express Fast/Gigabit Ethernet controller (rev 06)

is this a cmos glitch or linux?

The difference in lspci output is most likely just different labels in the different kernel versions. On way to test if there really is a difference is to run:

Code:

lspci -n

And compare output. The device codes should be indentical. Another thing you may want to check is:

Code:

lspci -k

This will let you check that the kernel module in use for each device seem correct.

However, the freezes and reboot issues seem quite worrying. Check the logs after such a freeze. /var/log/syslog or /var/log/messages. As I said in your other thread, I am not familiar with what logs are available on Xubuntu, but the different log files available in /var/log will hopefully have some useful information. You can post such logs here, but please use the code tags:

Code:

⁣[CODE]Post your log here[⁣/CODE]

Using code tags will make a long logs and code much easier to read.

Ok I found out what was causing me problems. It was dus to the fact that I had installed a 64-bit version of Xubuntu 14.04, even though this computer originally had Windows 8 installed I should imagine it was at the low end range for the OS. I have now installed the 32-bit version and all is almost well. But the wifi hardware on my computer causes the sound to stutter and echo so playing games or videos requires me to disable network. I will now have to find a way to remedy this glitch which may require looking at an upstream kernel.

If your hardware is not 64-bit then it is no wonder you were having issues when running a 64-bit OS. What surprises me is that you got it installed. To my knowledge you should not be able to boot a 64-bit OS on 32-bit hardware.

I have never heard about wifi interfering with sound. But your evidence seem quite strong since you say that the problems are gone if you disable wifi. Try to monitor your hardware temperatures.

I don't remember if you answered this before, but are you using a laptop? It really seems to me that your problem could be overheating. A lot of budget laptops have terrible cooling. If temperatures get a bit too high, the cpu will clock down. This would in turn cause your laptop to run slower, and stuttering sounds not too uncommon with a struggling cpu.