Can JetPack4.2 support PCIe discrete GPU ?

I want to plug a PCIe GPU card into Jetson AGX XAVIER to improve computing perfemence.
Can JetPack4.2 support PCIe discrete GPU now?
If not support,when will nvidia release the version?
Thanks

Currently only the embedded driver for the GPU integrated with memory controller works. PCIe cards do not work. I’ve heard there will be support in the future, but I doubt there is any specific release date.

Thanks for reply.