They are compatible, but you may not oc the fx8320 because there is not heatsink on the VRMs section.
Check the links, one is the LE and other is ASUS M5A97 R2.0 you can see the different that is in the upper side ( north) cpu socket. But if you can return it get the ASUS M5A97 R2.0.
LE
https://www.asus.com/media/global/products/j02VBoX5bQJxJu1B/uk5uOonv073sQVMN_500.jpg
ASUS M5A97 R2.0
http://www.asus.com/media/global/products/4bZFxu0IYyQ1DSfB/IiRK8LenGsnqrEZh_500.jpg
Here is from http://pcpartpicker.com, if they are not compatible they will tell you. http://pcpartpicker.com/parts/partlist/
PCPartPicker part list:
http://pcpartpicker.com/p/llFO
Price breakdown by merchant: http://pcpartpicker.com/p/llFO/by_merchant/
Benchmarks: http://pcpartpicker.com/p/llFO/benchmarks/
CPU: AMD FX-8320 3.5GHz 8-Core Processor ($159.97 @ OutletPC)
Motherboard: Asus M5A97 LE R2.0 ATX AM3+ Motherboard ($69.99 @ Newegg)
Total: $229.96
(Prices include shipping, taxes, and discounts when available.)
(Generated by PCPartPicker 2014-05-06 12:05 EDT-0400)
Here is the cpu support list https://www.asus.com/Motherboards/M5A97_LE_R20/HelpDesk_CPU/ , as long as the MB has the 1006 version ( came out 10/22/2012).