I have similar problem too.
I just bought new laptop (Acer aspire 4755g, Intel Core i5 2430-2,4Ghz) .
using windows 7 home premium 64 bit.
after I install company of heroes in C

rogram files (x86),
it pop up said
"failed to find a supported hardware rendering device. ensure that your system meet requirement of COH.
Verify that DirectX is properly installed that you have the latest
drivers for your system"
I check through DXdiag. my VGA is NVIDIA Geforce 540 2 GB and it is already installed DirectX 11.
anyone could help?