They will work , but run as USB 2.0 with this adapter.
http://www.newegg.com/Product/Product.aspx?Item=N82E16812201039&nm_mc=KNC-GoogleAdwords-PC&cm_mmc=KNC-GoogleAdwords-PC-_-pla-_-USB+Converters-_-N82E16812201039&gclid=CIOlwJ2d7sgCFUqRHwodqiAGrA&gclsrc=aw.ds
Apevia CVTUSB32 USB 3.0 to USB 2.0 Converter Cable