Tried Nvidia's GTX 1080 - still no external GPU on a Pi

Earlier today I did a livestream on my YouTube channel to attempt using an Nvidia GeForce GTX 1080 on a Raspberry Pi Compute Module 4.

MSI Nvidia GeForce GTX 1080 Graphics Card GPU

As with all my testing, I'm documenting everything I learn in this GitHub issue, which is part of the Raspberry Pi PCI Express Card Database website.

It's only been a few hours, but I've already gotten good suggestions for better debugging than I was able to do on the stream. And someone pointed out it might be the case, due to 32-bit memory limitations on the BCM2711's PCIe bus, that no GPU with more than 4 GB of onboard RAM could work. Though it's hard to confirm there'd be no software workaround—even 1 and 2 GB graphics cards (AMD and Nvidia) are crashing the kernel in similar ways.

The full livestream is available on replay and is embedded below:

Three more graphics cards on the Raspberry Pi CM4

Last year I tested two older graphics cards—a Radeon 5450 and a GeForce GT710—on a Raspberry Pi Compute Module 4.

Jeff Geerling holds NVidia and ASRock Rack GPU and Raspberry Pi Compute Module 4 with quizzical look

This year, I've been testing three more graphics cards—a GeForce GTX 750 Ti, a Radeon RX 550, and the diminutive ASRock Rack M2_VGA.

The Compute Module 4, if you didn't know already, exposes the BCM2711's single PCI express lane, and the official IO Board has a nice, standard, 1x PCIe slot into which you can plug any PCI express device.

External GPUs and the Raspberry Pi Compute Module 4

The Raspberry Pi Compute Module 4 eschews a built-in USB 3.0 controller and exposes a 1x PCI Express lane.

The slightly older Raspberry Pi 4 model B could be hacked to get access to the PCIe lane (sacrificing the VL805 USB 3.0 controller chip in the process), but it was a bit of a delicate operation and only a few daring souls tried it.

Raspberry Pi Compute Module 4 with Zotac Nvidia GeForce GT 710 GPU

Watch this video for more detail about my experience using these GPUs on the CM4:
GPUs on a Raspberry Pi Compute Module 4!

What does Nvidia buying ARM mean for Raspberry Pi?

Over the weekend, Nvidia confirmed it would purchase ARM from Softbank for $40 billion.

Now, what is ARM, why is Nvidia buying it, and what does any of this have to do with the Raspberry Pi?

Well, let's start with ARM.

This blog post also has a video version to go along with it.

What is ARM?

ARM can refer to a number of things, but let's start by talking about the company, Arm Holdings. They have lineage dating back to Acorn computers, a British computer manufacturer founded in the late 1970s that designed the first 'Acorn RISC Machine architecture' chips, AKA 'ARM'.

BBC Micro Minicomputer - Source: Wikipedia

Glitchy Video and Freezes on MacBook Pros

I've had a few friends report strange issues with their MacBook Pro laptops. Often they would report that the video signal on either an internal or external display becomes 'glitchy' or 'jumpy'. I initially thought it could be a connection issue, as I've seen many a VGA cable that becomes loose cause weird sync issues. However, they also reported that the cursor continued to work normally, moving around when they were moving the mouse/trackpad.

MacBook Pro Graphics Glitch
Doesn't look too nice...

I typically recommend people take these sorts of issues to the Genius Bar at an Apple Store, especially since the problem isn't easy to replicate when I take a minute or two to look at the laptop—often the problem only happens after constantly using the computer for more than half an hour.

However, I finally got to experience the problem first-hand, when my sister brought me her laptop and I used it for an evening of blogging and browsing. After half an hour or so, the screen started getting quite jittery (click through to view video and read more):