Hardware advice

[TheDreadPirate]

A search for "HP 6300" is returning a pretty wide list of possible configurations. It really depends on what the actual specs are. You said you bought it surplus several years ago, which means it was old back then, so its even older now. It may not be suitable, or even able to, accept an Intel Arc GPU. Even if it could accept an Arc GPU, the CPU would hold it back (audio transcodes on the CPU).

If you don't need AV1 encoding, a lot of people have gotten Beelink Intel N100 equipped mini PCs and have praised the performance and performance per watt.

https://www.amazon.com/Beelink-S12-Pro-G...B0BW8JSQCH

Since you have a NAS already, you don't have to worry about about directly attaching hard drives to the mini PC.

Honestly, the price for that is pretty amazing considering it already has RAM and a SSD. I had to do a double take when I noticed it already had those. I thought it was a bare bones system.