I will be driving my 03 1.8t 5mt Jetta into the ground, thank you very much.

Ok, let’s say that’s true. Which of the alternatives do you genuinely think are better?

It is 100% a great idea to see how you feel about the concept of self-hosting with an old machine. If it’s really old (and I’m talking like anything from before about 2008-2010), perhaps consider snagging an old “tiny”/1L-class box from eBay for cheap. Dell, HP, and Lenovo units can be found for WAY under $100 all the time, and slightly more modern units can still be had at a reasonable price, depending on the model. They’re great platforms to play around with. Just shove a cheap SSD in there and play with it.

Source: an old m920q with an i5-8500T is running pfSense for my home network

Time for a repo fork?

I think your best bet will be an SFF/USFF/1L box used on eBay. The tiny/1L ones mostly have energy-efficient CPUs (like intel T-suffix SKUs), but they also don’t support the SATA connections you specified (unless you go for an external USBC/TB3 enclosure, which many people do)

Yeah, though the advantage of the T sku CPUs is that they have ultra low tdp. Great for 24/7 boxes.

So the big gain you’ll likely see is bang/capability for the money. If you’re careful and wait for a deal, can usually find 1L boxes for like $50-75. Get a cheap m2 ssd (and back up your confs regularly if you’re not running raid z2). The nic is going to be anywhere from about 30-70, but you’ll need to do your research on exactly what capabilities the thing you’re buying has (for example: I had a false start initially, because the RJ45 10G nic I found couldn’t negotiate at 2.5G (what I’m running now), and it’s actually pretty hard to find a 2.5G enterprise nic. Make sure the nic is intel, too - none of that Realtek crap, which is less performant and often has stupid driver crap you have to deal with under Linux and BSD (pfSense). You may want to spend a few extra bucks and get the Lenovo external pcie mount plate/bracket for aesthetics/“don’t stick your fingies in here”, and you will need an adapter for Lenovo’s proprietary PCIe-but-not-a-standard-PCIe-port thing.

i5 8500T. I don’t recall exactly what the power draw is, but iirc it’s in the 20-30w range - admittedly a bit high, but that’s likely due to the old LSI nic in there which is technically an enterprise-grade card, and not terribly power efficient. Nonetheless, works great, full 10G speed, no thermal issues in the last few months I’ve been running it (in the summer, so I should be totally fine in the winter).

Go on eBay and look for “tiny” or USFF boxes. Dell, HP, and Lenovo make various models of 1L units that are commonly available. Just make sure to do some research on what the specific hardware capabilities are to make sure they satisfy your needs.

Source: my router is a Lenovo m920q tiny with an eBay dual SFP+ 10G NIC running pfSense 2.7.

As long as it’s not error or critical to touch, you should be good.

What temps were you seeing before adding the fan?

oh, you.