TOPIC: NVIDIA
Keeping a graphical eye on CPU temperature and power consumption on the Linux command line
20th March 2025Following my main workstation upgrade in January, some extra monitoring has been needed. This follows on from the experience with building its predecessor more than three years ago.
Being able to do this in a terminal session keeps things lightweight, and I have done that with text displays like what you see below using a combination of sensors and nvidia-smi in the following command:
watch -n 2 "sensors | grep -i 'k10'; sensors | grep -i 'tdie'; sensors | grep -i 'tctl'; echo "" | tee /dev/fd/2; nvidia-smi"
Everything is done within a watch command that refreshes the display every two seconds. Then, the panels are built up by a succession of commands separated with semicolons, one for each portion of the display. The grep command is used to pick out the desired output of the sensors command that is piped to it; doing that twice gets us two lines. The next command, echo "" | tee /dev/fd/2, adds an extra line by sending a space to STDERR output before the output of nvidia-smi is displayed. The result can be seen in the screenshot below.
However, I also came across a more graphical way to do things using commands like turbostat or sensors along with AWK programming and ttyplot. Using the temperature output from the above and converting that needs the following:
while true; do sensors | grep -i 'tctl' | awk '{ printf("%.2f\n", $2); fflush(); }'; sleep 2; done | ttyplot -s 100 -t "CPU Temperature (Tctl)" -u "°C"
This is done in an infinite while loop to keep things refreshing; the watch command does not work for piping output from the sensors command to both the awk and ttyplot commands in sequence and on a repeating, periodic basis. The awk command takes the second field from the input text, formats it to two places of decimals and prints it before flushing the output buffer afterwards. The ttyplot command then plots those numbers on the plot seen below in the screenshot with a y-axis scaled to a maximum of 100 (-s), units of °C (-u) and a title of CPU Temperature (Tctl) (-t).
A similar thing can be done for the CPU wattage, which is how I learned of the graphical display possibilities in the first place. The command follows:
sudo turbostat --Summary --quiet --show PkgWatt --interval 1 | sudo awk '{ printf("%.2f\n", $1); fflush(); }' | sudo ttyplot -s 200 -t "Turbostat - CPU Power (watts)" -u "watts"
Handily, the turbostat can be made to update every so often (every second in the command above), avoiding the need for any infinite while loop. Since only a summary is needed for the wattage, all other output can be suppressed, though everything needs to work using superuser privileges, unlike the sensors command earlier. Then, awk is used like before to process the wattage for plotting; the first field is what is being picked out here. After that, ttyplot displays the plot seen in the screenshot below with appropriate title, units and scaling. All works with output from one command acting as input to another using pipes.
All of this offers a lightweight way to keep an eye on system load, with the top command showing the impact of different processes if required. While there are graphical tools for some things, command line possibilities cannot be overlooked either.
Upheaval and miniaturisation
4th March 2025The ongoing AI boom got me refreshing my computer assets. One was a hefty upgrade to my main workstation, still powered by Linux. Along the way, I learned a few lessons:
- Processing with LLM's only works on a graphics card when everything can remain within its onboard memory. It is all too easy to revert to system memory and CPU usage, given the amount of memory you get on consumer graphics cards. That applies even with the latest and greatest from Nvidia, when the main use case is for gaming. Things become prohibitively expensive when you go on from there.
- Even with water cooling, keeping a top of the range CPU cool and its fans running quietly remains a challenge, more so than when I last went for a major upgrade. It takes time for things to settle down.
- My Iiyama monitor now feels flaky with input from the latest technology. This is enough to make me look for a replacement, and it is waking up from dormancy that is the real issue. While it was always slow, plugging out from mains electricity and then back in again is a hack that is needed all too often.
- KVM switches may need upgrading to work with the latest graphical input. The monitor may have been a culprit with the problems that I was getting, yet things were smoother once I replaced the unit that I had been using with another that is more modern.
- AMD Ryzen 9 chips now have onboard graphics, a boon when things are not proceeding too well with a dedicated graphics card. Even though this was not the case when the last major upgrade happened, there were no issues like what I faced this time around.
- Having LED's on a motherboard to tell what might be stopping system startup is invaluable. This helped in July 2021 and averted confusion this time around as well. While only four of them were on offer, knowing which of CPU, DRAM, GPU or system boot needs attention is a big help.
- Optical drives are not needed any longer. Booting off a USB drive was enough to get Linux Mint installed, once I got the image loaded on there properly. Rufus got used, and I needed to select the low-level writing option before things proceeded as I had hoped.
Just like 2021, the 2025 upgrade cycle needed a few weeks for everything to settle down. The previous cycle was more challenging, and this was not just because of an accompanying heatwave. The latest one was not so bedevilled.
Given the above, one might be tempted to go for a less arduous path, like my acquisition of an iMac last year for another place that I own. After all, a Mac Mini packs in quite a lot of power, and it is not the only miniature option. Now that I have one, I have moved image processing off the workstation and onto it. The images are stored on the Linux machine and edited on the Mac, which has plenty of memory and storage of its own. There is also an M4 chip, so processing power is not lacking either.
It could have been used for work affairs, yet I acquired a Geekom A8 for just that. Though seeking work as I write this, my being an incorporated freelancer means that having a dedicated machine that uses my main monitor has its advantages. Virtualisation can allow drift from business affairs to business matters, that is not so easy when a separate machine is involved. There is no shortage of power either with an AMD Ryzen 9 8945HS and Radeon 780M Graphics on board. Add in 32 GB of memory and 2 TB of storage and all is commodious. It can be surprising what a small package can do.
The Iiyama's travails also pop up with these smaller machines, less so on the Geekom than with the Mac. The latter needs the HDMI cable to be removed and reinserted after a delay to sort out things. Maybe that new monitor may not be such an off the wall idea after all.
Dropping back to a full screen terminal session from a desktop one in Linux
29th May 2014There are times when you might need to access a full screen terminal from a Linux graphical desktop. For example, I have needed this when installing Nvidia's graphics drivers on Ubuntu or Linux Mint. Another instance occurred on Arch Linux when a Cinnamon desktop update prevented me from opening a terminal window. The full screen command let me install an alternative terminal emulator, with Tech Drive-in's list proving helpful. Similar issues might need fixing on FreeBSD installations. These latter examples happened within VirtualBox, which has special requirements for accessing full screen command line sessions, which I'll explain later.
When running Linux on a physical PC, press CTRL + ALT + F1 to enter a full screen terminal and CTRL + ALT + F7 to return to the graphical desktop. In a Linux VirtualBox guest with a Linux host, these shortcuts affect the host instead. For the guest OS, use [Host Key] + F1 to enter a full screen terminal and [Host Key] + F7 to return to the graphical desktop. The default Host Key is the right CTRL key, unless you've changed it.
X sessions in GNOME and Cinnamon desktop environments support this functionality, but I can't confirm it works with alternatives like Wayland. Hopefully, this feature extends to other setups, as terminal sessions are occasionally needed for system recovery. Such mishaps are thankfully rare and should be virtually non-existent for most users.
A need to update graphics hardware
16th June 2013As someone who doesn't play computer games, I rarely prioritise graphics card upgrades. Yet, I recently upgraded graphics cards in two of my PCs despite nothing being broken. My backup machine, built nearly four years ago, has run multiple Linux distributions. It uses an ASRock K10N78 motherboard from MicroDirect with an integrated NVIDIA graphics chip that performs adequately, if not exceptionally. The only issue was slightly poor text rendering in web browsers, but this alone wasn't enough to justify adding a dedicated graphics card.
More recently, I ran into trouble with Sabayon 13.04 with only the 2D variant of the Cinnamon desktop environment working on it and things getting totally non-functional when a full re-installation of the GNOME edition was attempted. Everything went fine until I added the latest updates to the system, when a reboot revealed that it was impossible to boot into a desktop environment. Some will relish this as a challenge, but I need to admit that I am not one of those. In fact, I tried out two Arch-based distros on the same PC and got the same results following a system update on each. So, my explorations of Antergos and Manjaro have to continue in virtual machines instead.
When I tried Linux Mint 15 Cinnamon, it worked perfectly. However, newer distributions with systemd didn't work with my onboard NVIDIA graphics. Since systemd will likely come to Linux Mint eventually, I decided to add a dedicated graphics card. Based on good past experiences with Radeon, I chose an AMD Radeon HD 6450 from PC World, confirming it had Linux driver support. Installation was simple: power off, insert card, close case, power on. Later, I configured the BIOS to prioritise PCI Express graphics, though this step wasn't necessary. I then used Linux Mint's Additional Driver applet to install the proprietary driver and restarted. To improve web browser font rendering, I selected full RGBA hinting in the Fonts applet. The improvement was obvious, though still not as good as on my main machine. Overall, the upgrade improved performance and future-proofed my system.
After upgrading my standby machine, I examined my main PC. It has both onboard Radeon graphics and an added Radeon 4650 card. Ubuntu GNOME 12.10 and 13.04 weren't providing 3D support to VMware Player, which complained when virtual machines were configured for 3D. Installing the latest fglrx driver only made things worse, leaving me with just a command line instead of a graphical interface. The only fix was to run one of the following commands and reboot:
sudo apt-get remove fglrx
sudo apt-get remove fglrx-updates
Looking at the AMD website revealed that they no longer support 2000, 3000 or 4000 series Radeon cards with their latest Catalyst driver, the last version that did not install on my machine since it was built for version 3.4.x of the Linux kernel. A new graphics card then was in order if I wanted 3D graphics in VMware VM's and both GNOME and Cinnamon appear to need this capability. Another ASUS card, a Radeon HD 6670, duly was acquired and installed in a manner similar to the Radeon HD 6450 on the standby PC. Apart from not needing to alter the font rendering (there is a Font tab on the Gnome Tweak Tool where this can be set), the only real exception was to add the Jockey software to my main PC for installation of the proprietary Radeon driver. The following command does this:
sudo apt-get install jockey-kde
After completing installation, I ran the jockey-kde command and selected the first driver option. Upon restart, the system worked properly except for an AMD message in the bottom-right corner warning about unrecognised hardware. Since there were two identical entries in the Jockey list, I tried the second option. After restarting, the incompatibility message disappeared and everything functioned correctly. VMware even ran virtual machines with 3D support without any errors, confirming the upgrade had solved my problem.
Hearing of someone doing two PC graphics card upgrades during a single weekend may make you see them as an enthusiast, but my disinterest in computer gaming belies this. Maybe it highlights that Linux operating systems need 3D more than might be expected. The Cinnamon desktop environment now issues messages if it is operating in 2D mode with software 3D rendering and GNOME always had the tendency to fall back to classic mode, as it had been doing when Sabayon was installed on my standby PC. However, there remain cases where Linux can rejuvenate older hardware and I installed Lubuntu onto a machine with 10-year-old technology on there (an 1100 MHz Athlon CPU, 1GB of RAM and 60GB of hard drive space in a case dating from 1998) and it works surprisingly well too.
It appears that having fancier desktop environments like GNOME Shell and Cinnamon means having the hardware on which it could run. For a while, I have been tempted by the possibility of a new PC, since even my main machine is not far from four years old either. However, I also spied a CPU, motherboard and RAM bundle featuring an Intel Core i5-4670 CPU, 8GB of Corsair Vengeance Pro Blue memory and a Gigabyte Z87-HD3 ATX motherboard included as part of a pre-built bundle (with a heat sink and fan for the CPU) for around £420. Even for someone who has used AMD CPU's since 1998, that does look tempting, but I'll hold off before making any such upgrade decisions. Apart from exercising sensible spending restraint, waiting for Linux UEFI support to mature a little more may be no bad idea either.
Update 2013-06-23: The new graphics card in my main machine works well and has reduced system error messages; Ubuntu GNOME 13.04 likely had issues with my old card. On my standby machine, I found and removed a rogue .fonts.conf file in my home directory, which dramatically improved font display. If you find this file on your system, consider removing or renaming it to see if it helps. Alternatively, adjusting font rendering settings can improve display quality, even on older systems like Debian 6 with GNOME 2. I may test these improvements on Debian 7.1 in the future.
Changing from to Nvidia Graphics Drivers on Linux Mint Debian Edition 64-bit
22nd April 2012One way of doing this is to go to the Nvidia website and download the latest file from the relevant page on there. Then, the next stage is to restart your PC and choose rescue mode instead of the more usual graphical option. This drops you onto a command shell that is requesting your root password. Once this is done, you can move onto the next stage of the exercise. Migrate to the directory where the *.run file is located and issue a command similar to the following:
bash NVIDIA-Linux-x86_64-295.40.run
The above was the latest file available at the time of writing, which may have changed by the time that you read this. If the executable asks to modify your X configuration file, I believe that the best course is to let it do that. Editing it yourself or running nvidia-xconfig are alternative approaches if you so prefer.
Since proprietary Nvidia drivers are included in the repositories for Linux Mint Debian Edition, that may be a better course of action since you will get updates through normal system update channels. Then, the course of action is to start by issuing the following installation commands:
sudo apt-get install module-assistant
sudo apt-get install nvidia-kernel-common
sudo apt-get install nvidia-glx
sudo apt-get install kernel-source-NVIDIA
sudo apt-get install nvidia-xconfig
Once those have completed, issuing the following in turn will complete the job ahead of a reboot:
sudo m-a a-i nvidia
sudo modprobe nvidia
sudo nvidia-xconfig
If you reboot before running the above like I did, you will get a black screen with a flashing cursor instead of a full desktop because X failed to load. Then, the remedy is to reboot the machine and choose the rescue mode option, provide the root password and issue the three commands (at this point, the sudo prefix can be dropped because it's unneeded) then. Another reboot will see order restored and the new driver in place. Running the following at that point will do a check on things, as will be the general appearance of everything:
glxinfo | grep render