Already touched this topic barely in another thread
https://lists.cinelerra-gg.org/pipermail/cin/2023-December/007346.html

But so many SW and HW pieces are mentioned around, it is almost a full-time reading and study:
VAAPI, MESA, VULKAN, Intel Quick Sync Video etc......

I realize my aging hardware which is fast enough for other tasks, needs some "AV1 upgrade", if possible.

But first I wonder, what is expected possible to do (obtain) with AV1 de-/encoding on my existing 64bit hardware:

1) laptop 2018: Dell XPS 13-9370: quad core i7-8550U CPU (8. gen Kabylake) and Intel UHD Graphics

2) WS infinity:  MSI Z170A mobo:  quad core i7-6700K CPU (6. gen Skylake), NVIDIA GeForce GT-730 graphics

A budget friendly first "AV1 HW upgrade" of the workstation 2) if possible, would be to add a new GPU as Intel Arc A380.
But the question is if this will work at all on that much older (2015) Skylake platform with i7-6700K CPU?
I've seen CPU bottlenecks has been mentioned and that Arc A380 is targeted at newer generations CPU ...

• Featuring 8 Xe-cores, the A380 supports PCI Express 4.0 and has a total board power (TBP) of 75W. The graphics card is equipped with 6GB GDDR6 memory and a graphics memory interface of 96 bits, providing a memory bandwidth of 186GB/s.
• Bus interface A380:         PCIe 4.0 x8 and for >=A580: PCIe 4.0 x16

References:
AV1 Encoding on a Budget: The Intel Arc A380 Approach
https://medium.com/@contact_45426/av1-encoding-on-a-budget-the-intel-arc-a380-approach-d72367f2f349
https://history-computer.com/intel-arc-a380-full-review-of-intels-entry-level-gpu/

AV1 fixed-function hardware encoder is included in Alchemist GPUs as part of the Intel Quick Sync Video core.
https://en.wikipedia.org/wiki/Intel_Arc#Alchemist
https://en.wikipedia.org/wiki/AV1#Hardware
https://en.wikipedia.org/wiki/Intel_Quick_Sync_Video#Hardware_decoding_and_encoding