Are DI/O cards like the 651x compatible with PCIe 1x?

Hi,

This may be a bit of a stupid question, but this is my first outing with NI and yet I have somehow been given some amount of responsibility for a very strange procurement process.  Hopefully the question is simple to answer and that will mitigate its possible dumbness.

Are cards like the NI 651x (http://www.ni.com/datasheet/pdf/en/ds-105) compatible with PCIe 1x?  From the image it looks like they are designed to run on PCIe 16x, but since speed is not a major concern I was wondering if it would install and run normally on PCIe 1x.

I am limited in procurement to a default, organization wide Tower PC build, whose motherboard has two PCIe 16x and two PCIe 1x.  Since I will likely need three cards, I was hoping that it would be compatbile with the PCIe 1x slot and would save us the special procurement order form hassle.

Thanks for any help!