Intel N100 Radxa X4 First Thoughts

227

It only feels like the beginning of the week since Radxa announced their Intel N100-based Radxa x4 Single Board Computer and thanks to the wonders of express global shipping, I’ve had one in my hands since lunchtime.

It’s the first time in a long, long time that I find myself being excited about an SBC and I feel it’s for a good reason? Here we have a (more or less) Raspberry Pi 5 form factor board with an x86 processor, the Intel N100. This means that I was able to grab the Windows 11 ISO and install it. I was able to go to Debian’s homepage, grab the latest ISO and just, well, install it?

I’m going to try something slightly different though and rather than slam you with 20 graphs, I’m going to approach it more as if you were asking me what I thought about it face-to-face. I’ll include some data, but it’s going to be my first thoughts upon opening and playing with the Radxa x4 first and foremost. It may get a little rambly but you all expect that from me at this point.

Radxa x4 Specifications

As a quick overview, the Radxa x4 offers the following:

• Intel N100 CPU (4 Alderlake CPU cores, up to 3.4GHz)
• Intel UHD Graphics (750MHz)
• 4/8/12/16GB LPDDR5 4786MT/s
• 2.5Gbit RJ45 Ethernet (with PoE support via HAT)
• M.2 M-Key connection for M.2 2230 NVMe drives
• 12V USB-C Power Delivery Input
• 3x USB-A 3.2 (10Gbps) ports, 1x USB-A 2.0
• WiFi 5 & BT5, or WiFi 6 & BT5.2 (the latter on 8GB RAM models and up)
• 2x Micro HDMI (up to 4K60)
• Raspberry Pi RP2040 to control the 40-pin GPIO headers
• Fan & RTC Battery headers
• 3.5mm Headphone & Microphone Jack
• eMMC is available either to solder yourself or when you order a SKU that includes it

The inclusion of the RP2040 for the GPIO header control is a great move. Long before I wrote the ARM vs N100 piece (comparing an RK3588 to an Intel 100 Mini PC) during the Raspberry Pi shortages everyone was screaming “Just buy a mini PC!!!” but that really didn’t help anyone who wanted or needed to interface with the Raspberry Pi’s GPIO for their projects. Now, you have the best of both worlds but will Radxa nurture the product and ecosystem in a way that will pose a legitimate thread to those on the fence about the Raspberry Pi 5?

Out of the Box

I received my package with the Radxa x4, its PoE+ HAT (there’s a new, specific HAT for the x4), and the case/cooler hybrid they’ve got going on and there was a fun mix of packaging. I definitely prefer when vendors ship in plastic cases (sorry, I know) as they’re much more suited to stacking in my storage shelves.

Everything was as I expected inside. The case/cooler came with a thermal pad (more on that later) and 2 feet sticker things so you don’t have to have metal directly on a surface, the PoE HAT has standoffs pre-applied with extras in a bag, and the x4 board came with a pre-installed RTC battery and 2 WiFi antennas.

Initial Setup

For this post I’ve been using the official Pi 5 PSU (it offers 2.25A at 12V) and a WD_BLACK SN770M 2230 M.2 NVMe drive.

BIOS

I was fully expecting a BIOS offering 2-3 pages with 5 options per page given my experience with mini PCs (also rocking N100 CPUs) but upon first boot and jumping into the BIOS I was very pleasantly surprised. The screenshot below shows the American Megatrends BIOS built in April 2024, so really quite new!

If you dig a little deeper into the options, you’ll find you have the ability to really tweak the settings for most aspects of the system. I’ve included a preview of the CPU Power Management page, and the NVMe information/configuration page, but there are quite a few more!

Debian 12 (Bookworm)

I gave Debian a try first to see how things went and it was fairly uneventful. You just need to grab the relevant ISO (I took the net install option) and go through the installation process. I opted for GNOME as my desktop environment to look around and it was responsive, with most things working as expected.

The 2.5GbE network connection (supplied by an Intel I226-V NIC) was detected during installation, however, WiFi/BT wasn’t and that carried on once into the OS. WiFi drivers are always a bit picky though.

A 4K 60fps “HDR” video in the included Firefox ran extremely smoothly (in my opinion) with around 40 frames dropped during the 5min13s video. These were barely noticeable and the Radxa x4 happily chugged along. A quick try on Windows showed much the same in terms of minimal dropped frames.

I didn’t spend much more time in Debian as I wanted to see how Windows 11 would fare. Sorry, not sorry.

Windows 11

You’ll need to create a Windows media installation via their tool on another computer (or create installation media however you like) to get up and running but it’s quick and easy, and within a couple of minutes I had the Windows installation running nice and smoothly.

That is until we reached the network detection part where it was immediately apparent that there were no suitable network drivers within the default Windows installation media. Bit of a bummer, but if you hit SHIFT+F10 you’ll bring up a prompt that you can enter OOBE\BYPASSNRO in and hit enter. Once done, the installer will restart and when you get back to the network page it will offer you the option to skip without an internet connection.

Once you’re finally in Windows though, you’ll want to address the network driver issue. Luckily, Intel’s driver page has everything you need and you can download those on another device and copy them across with a USB drive or similar. When installed, you have yourself a little x4 ready to take on the world.

Quick Tests

Geekbench 6 for Windows

I’m not going to go through a full benchmarking suite here, but as I had Windows open, I thought I’d see how Geekbench 6 was looking. On the CPU side, we ended up with a 1007 single-core and a 2295 multi-core score. For the Intel GPU, we saw 3246 for OpenCL and 3710 on Vulkan.

A note for this section though, by default (and after changing the power plan) the maximum CPU frequency, even on single-core workloads was 2.9GHz. I likely need to dig into the BIOS a little more and make some changes to get the N100 running at its full speed. As a quick side note, changing the PL2 values to 6W from 25W made no difference for this benchmark and when run on Ubuntu, it got up to 3.1GHz and posted 1171 on single-core, and 2389 multi-core.

Networking

iperf3 between the Radxa x4 (on Windows) and my ROCK 5B (Debian) manages to saturate the 2.5Gbps connection in both directions so everything’s looking good there. WiFi didn’t install via Windows Update, nor was I able to quickly find a suitable driver so for this first thoughts post, WiFi gets a thumbs down, I’ll have to look into that later.

On Ubuntu though the WiFi chip shows up as a Realtek RTL8852BE adapter and worked during the Ubuntu installation process.

Power Draw

Under Windows 11 at idle with the default BIOS power settings (so the default power targets and Intel Speedstep enabled etc) I’m pulling 8 watts from the wall. This is with a basic keyboard, a Razer Deathadder (which does have an LED), 1x HDMI, 2.5GbE networking, and the WD_BLACK SN770M 500GB NVMe SSD.

If I yank out everything bar the power cable, idle power utilisation drops to around 6.8 watts, so you can save 1.2 watts if you want to run it headless I suppose?

If I then stress the Intel N100 and its GPU with OCCT and the Power Configuration tester (it stresses the CPU, RAM and GPU all at once) it quickly jumps to 27.3 watts and then drops down, likely because that’s at the limit of what the 12V/2.25A PSU (the official Raspberry Pi 5 PSU) can offer so for future testing, I’ll need to give it a slightly beefier power supply and see what it does. Stressing just the CPU and RAM results in 22.1 watts of power draw.

Temperatures

To cover the question I saw a few times on Twitter when it was announced, no, I’m going to recommend that you don’t leave the CPU open to the world and run it raw. The whole thing gets extremely hot, extremely quickly and the only way you’re going to be able to keep it somewhat under control is if you heavily throttle its power targets, in which case, what’s the point? You could probably make do with an ARM chip if that’s the plan.

Fortunately, I have the Radxa 4x Cooler/Case combo. It’s not strictly a case as it has open sides and an open bottom but it keeps it off the surface where you’ve placed it and it has a fan which is nice.

Unfortunately, the thermal pad was crumbling and ripping when I tried to apply it and I have no idea if that’s supposed to be normal or not? I was told that the thermal pad was rated for 13.8 watts, though I don’t think it’s quite enough for this setup. Perhaps things would be better when I figure out how to get the fan to operate from behind the RP2040.

I’ll revisit this topic in the follow-up piece but at first glance, I can actually see light between the board/thermal pad/cooler in places so that pad feels like it’s either slightly too thin or something’s happened to the pad that I have here and that hampers cooling.

Power over Ethernet

One of the selling points of this SBC was that the 2.5GbE port was PoE-compatible with a HAT, to the point where Radxa made a modified version of their PoE+ HAT to work specifically with the x4. After finding my go-to cable wouldn’t do power and networking, I found one that worked and booted up fine. The second I hit it with a benchmark load it reset. Thinking the Power Limit 2 (PL2) may have been the problem with it set to 25W, I dropped it to 15W but nope, same problem.

Was my 2.5Gbit PoE switch to blame? It was a no-name unit from AliExpress, so possibly? I switched (hehe) over to my UniFi PoE switch to see if that changed anything and what do you know, it was able to handle the spike just fine with the PL2 set to 15W. Would the cheap PoE switch handle it if it was set to 6W? It does, so that’s good to know!

Summary

Overall, I still think it’s a very good product but it has things that need to be looked at and that will likely be covered by documentation that (I hope) will be on the way soon.

For the most part everything is working as expected. You have the ease of using whichever ISO you can find (though you may have a couple of driver issues to work around depending on what OS you’re looking to use. The cooler leaves a little to be desired, and when you have the PoE HAT installed too, your poor NVMe drive has around 1-2mm between it and the WiFi chip below, and then 3-4mm between it and the HAT above. When I get the fan on the HAT working this will alleviate a little of that pain.

I’ll work a bit more on benchmarking during the week once a bit more information comes out and I’ve tinkered a bit more but for now, it’s almost there, and I look forward to seeing what I can do in the next week or so.

For the curious, too, an sbc-bench run on Ubuntu Server 24 (on kernel 6.8.0-39 with all BIOS settings default bar the 6W PL2) can be found at https://0x0.st/Xf2I.bin

If you have any particular benchmark requests or things you want me to check out, let me know either in the comments or on Twitter and I’ll take a look!