B450 chipset PCIE lane availability for GPU + M.2

Hi,



I am planning to build my system with Ryzen 5 3600 in a B450 mobo(My choice are ASRock B450M Pro4 or MSI B450M Pro-VDH Max)



Now I am also using a GTX 1050 TI GPU with it. So if I Install a M.2 NVME SSD, as far as I know that B450 mobo dont have its own PCIE 3.0 x4 lanes for M.2 slot. So it uses CPU's lanes for the same. So now, if I install it, will my GPU will run at x8 lanes? or My GPU will continue to to run at x16? But can it be possible, will the B450 be able to use 4 lanes from my CPU's(3000 series ryzen) total 20!

Yes GTX 1050 TI will never use full capacity of 16 lanes. But my question is whatever the GPU is, will it be able to use all 16 lanes on B450 mobo with M.2 NvME SSD in it?