You should be fine. It will be compatible as long as the motherboard has a PCI-E slot, but the speed of the PCI_E slot can make a big difference. If this is a actively working PC, just download Speccy portable and check the motherboard section for PCI-E x16 or PCI-E x8. If you have either of those, it will work. Although as implied, an x16 slot provides double the bandwidth, so if you only have an x8 slot it will probably bottleneck the graphics card.
Dont worry about the CPU. Thats only going to be a bottleneck in cpu intensive games with lots of physics.
https://www.piriform.com/speccy/builds