Please help.

I have an asrock x299 oc formula motherboard which I use as a workstation for my job and I am upgrading to either

core i9 9980xe (skylake 44 pcie lanes) or
10980 (cascade lake 48 pcie lanes) cpu.

The motherboard originally was built when 7th gen cpus were being sold. The layout of physical pcie 3.0 slot size is

(x16;x1(pcie vers2.0);x16;x16;x16;x4;x16);

the available logical lanes per slot are either

(x16;x1;x0;x0;x16;x4;x8) or

I currently have

slot4=usb3.0 adapter card
slot5=usb3.0 adapter card
slot6=thunderbolt card (has to be in slot 6)

I want to add a used tesla k80 gpgpu which takes up two adjacent slots. the specs for the tesla say it requires pcie 3.0 x16.

(Question 1)
I assume you would put the cards like this:

slot2=overlapped by tesla
slot3= x0 lanes so empty
slot4= x0 lanes so empty
slot7=usb 3.0

Does this sound okay?

(Question 2)
I sacrificed slots 3 and 4 but what would happen if I put a card in there, would they all switch to
or is the rule that the total number of lanes has to add up to 44 and a card in slot 3 or 4 would grab lanes from another slot like 7?

what would happen if I had the core i9 10980 cpu which has 48 pcie lanes? would I get to use all 48 lanes? The motherboard was made when the max was 44 lanes.

Thank you :-) I can't find a great explanation of how this works and I have tried !!!!

Update: the asrock tech support said:
slots 1 and 3 are shared (x8x8) if co-existed.
slots 4 and 5 are shared (x8x8) if co-existed.
if using two full x16 pcie slots with x16 lanes each, use slot1,slot5
slot7 is always x8.
with 48 lane cpu, the rules are same (looks like you don't get to use more lanes).

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