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The BC-250 has no video encoder. It can still stream your games.

The BC-250 is a cheap little gaming PC built on a binned PS5 board. There's one catch for streaming: its video encoder and decoder don't work. Most streaming hosts stop right there. punktfunk ships PyroWave, a codec that runs on the GPU's shader cores instead, so a BC-250 can still stream to your couch over a cable.

The BC-250 is one of the best deals in PC gaming right now. It's basically a PS5 board that didn't make the cut: six Zen 2 cores, PS5-class graphics and 16 GB of fast GDDR6, for very little money. People put them in a small case, install Linux, and end up with a surprisingly capable gaming box.

Then they try to stream from it, and hit a wall.

The missing piece

A normal GPU has two jobs. It draws your game, and it has a small, separate block of silicon for video. That block turns frames into H.264, HEVC or AV1, and turns them back again on the other end. NVIDIA calls theirs NVENC. AMD calls it VCN. Every popular streaming host leans on it, because it's fast and it barely touches the rest of the chip.

On the BC-250, that block is out. Nothing to encode with, nothing to decode with. The decoder half matters less for a host, since the client does the decoding. The encoder half is the problem.

The usual fallback is a software encoder on the CPU. That's a rough trade on six cores that are already running your game. The game loses CPU time, and the stream still lags behind.

A codec that doesn't need a video engine

punktfunk ships a different kind of codec called PyroWave. It was written by Hans-Kristian Arntzen and it's open source. Instead of the video block, it runs as plain Vulkan compute shaders, the same kind of GPU work a game does. The BC-250's GPU has plenty of that.

It works like JPEG 2000 on fast-forward. Every frame is compressed on its own with a wavelet transform, with no references to earlier frames. Two nice things fall out of that:

  • It's fast. On a desktop RTX 5070 Ti, a 1080p frame encodes in about 0.15 ms and decodes in about 0.07 ms. We haven't clocked a BC-250 yet, but even a GPU a fraction of that size finishes long before the next frame is due.
  • Every frame is a keyframe. Drop a packet and you lose one frame. No smeared picture, no half-second stutter while the stream waits for a fresh keyframe.

punktfunk clients on Linux, Windows, Apple devices and 64-bit Android all decode it.

The catch: it wants a cable

PyroWave trades bandwidth for speed, and the trade is steep. Roughly:

  • 1080p at 60 fps: about 200 Mbps
  • 1080p at 120 fps: about 400 Mbps
  • 1440p at 60 fps: about 355 Mbps
  • 1440p at 120 fps: about 710 Mbps

Gigabit Ethernet carries about 940 Mbps of real payload, so a cable handles everything up to 1440p at 120 fps. 4K at 60 wants 2.5 Gbit networking. And don't try it over Wi-Fi. That's why the setting is literally called "PyroWave (wired LAN)".

Two smaller things to know:

  • It shares the GPU with your game. PyroWave encodes on the same shader cores the game uses. punktfunk gives the encoder real-time priority on the GPU so it doesn't queue behind the game (the packages set that up for you), but a game that maxes out the GPU will feel a small tax. We wrote about that fight in low-latency streaming under GPU load.
  • It's SDR on Linux. PyroWave HDR needs a Windows host today, and a BC-250 is a Linux box. Crisp 4:4:4 color works, for about 1.6× the bitrate.

Setting it up

  1. Install the punktfunk host on the BC-250. The download page has the one-liner.
  2. Plug the BC-250 and your client into your network with cables.
  3. On the client, open Settings → Video codec and pick PyroWave (wired LAN).
  4. Start at 1080p or 1440p, 60 fps, and see how it feels.

Step 3 is the important one. punktfunk never picks PyroWave by itself. Leave the codec on Automatic and the host tries a hardware codec the BC-250 doesn't have. Set it once per client and you're done. The host side needs no setup at all.

So, is a BC-250 a good streaming host?

With a network cable, yes. It won't do 4K, it won't do HDR, and it won't stream over Wi-Fi. But for 1080p or 1440p to a docked Steam Deck, a laptop or the TV in the living room, it's a lot of streaming box for the money. Pick PyroWave on the client, keep it wired, and play.

The full details, including every client that supports it, are in the PyroWave docs.