Using a C1060 Card in a 8x Electrical Socket

My motherboard has two PCI-E 2.0 slots both 16x in physical size.

1 operates at 16x bandwidth, and the other at 8x bandwidth.

I currently have a GTS 250 card in the 1st 16X electrical slot.

I would like to buy a C1060 card to put into my other slot, but will I encounter any issues / speed reductions due to that it is only 8x pci-e in bandwidth?

I’m not sure what the question is…

If you put the card in a 16x slot with 8x bandwidth, then you will suffer a performance hit due to slower transfers between the card and host. The amount of that performance hit will depend on whatever applications you run (e.g. how much data they are transferring back and forth). For compute-intensive kernels, the loss will be less than that of transfer-intensive kernels.