[T] T80-Pro Mini PC as Potential Mainboard?

A project log for Tetent UMPC [gd0149]

Can I now make something better than a 2-in-1 laptop? Something that I can use outdoors?

kelvinakelvinA 06/15/2023 at 15:000 Comments

I remembered a mini PC I saw a while ago, but didn't know what it was called. Thankfully, "triple HDMI mini PC" was able to find it:

Now, this is great because it has all the IO I was really hoping for in a UMPC: dual ethernet, 10gbps USB and 3 HDMI ports for the 3 displays. It's also great because of the price. I'm not hopeful it's going to last, looking at price history, but sub £160 for this is a really attractive offer for the reasons I'll mention in this log. 

It looks like, if you time it, you could get the above config for sub £160.

As you can see, the internals of this are rather simple. The great part is that the entire thing is 87*87*40mm in volume (though, elsewhere it says 80*80*40). This should be able to fit in a build that looks only slightly taller and thicker than a standard Tetent.

Now I want to bring your attention to the laptop I called Deti:

I had this for 4 years, and honestly the only reason why I had to bounce and create #Teti [gd0022] was because it was falling apart. The 2-in-1 functionality basically broke after a Windows update 2 weeks after owning it, but that 360 hinge was still very useful... until it broke of the backplate that holds the screen up about 3 years down the line, and the £65 replacement only lasted another year. (and I broke the digitalizer in the process of installing it). The extra storage HDD failed at around 3 years in too, as did the stock charger. Basically, it was costing more and more to keep fixing it and I didn't want to spend more when I'd only be able to upgrade to 16GB of DDR4 down the line (12GB was installed).

But wait. The T8 Pro also only comes with 16gb of RAM (albeit DDR5 faster). 

Yes. That's not an issue... for £155. My issue is when laptop manufacturers are asking £900 and up for 16GB. In that price segment, I essentially make 32GB a mandatory requirement. 

Have you noticed something I haven't mentioned though? Processing power. I was FINE with the i7-7500U performance, and honestly the 11600K I have now didn't bring that much day-to-day performance other than speeding up the Fusion360 renderer, which is a multithreaded task. And look at these benchmarks:

CPU-wise, I'm getting comparable performance to a £900 (on clearance) laptop from 2017 for 40% of the TDP (6W vs 15W). 

It's a bit interesting to know though that the N100 only supports single channel memory. It's still faster, though:

N100 left, 7500U right. The 7500U also supports 32GB of memory, but every (touchscreen) laptop I could find could only be upgraded to max 16GB anyway.

My concern is a bit more with the GPU, looking at this:

The T8 Pro is advertised to be able to run 3 UHD displays, so 2 QHD + 1/2 FHD should be within it's ability. If it can run Fusion360 it's probably good enough for me. I looked to see if I could find more benchmarks, and I found this which shows that the 24EU's are about or slightly faster than UHD620, depending on the benchmark. Intel hasn't changed anything between Alder Lake and Jasper Lake EU's.

Looking at this, it does seem that the chip can actually boost way over 6W though. Anyway, it totally looks like Intel made the i7 of 7-years-ago here, and it's about 2/7ths the price of the lowest cost Framework+32G+2TB strategy. 

The T8-Pro looks great, though there isn't a 2TB option in the listing (even though it's supported). 1TB + OneDrive is probably fine. The BT is also only at 4.2, but that can be solved with a small internal USB dongle (or the Tetrinsics perhaps?) Ideally, the exposed ports for Leti would be everything minus 1 USB3 port (for internal connections to things such as the 5G modem and Tetrinsics), but that would require some HDMI switcher circuitry to direct the signal either to the inbuilt screens or external ones.

For a minimum-viable-product, all I'd really need to do is solder 2 wires to bypass the barrel jack connector. Then all the essentials can be exposed easily:

And if I really need to show my screen on a monitor (which I personally haven't needed to do), I can use a USB3.0 to HDMI adapter, which is capable of 1080P60. Otherwise, since the inbuilt input device is theoretically better than anything I'd be able to plug into a USB port anyway, the least I'd use USB for are USB headphones and the most I'd be doing is copying files from one HDD to another; in that case, 2 USB3.1 ports is just right.