Check
lspci -k | grep -A 2 -i "VGA"
01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] RV730 GL [FirePro V3750] Subsystem: Advanced Micro Devices, Inc. [AMD/ATI] RV730 GL [FirePro V3750] Kernel driver in use: radeon
lspci -k | grep -A 2 -i "VGA"
01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] RV730 GL [FirePro V3750] Subsystem: Advanced Micro Devices, Inc. [AMD/ATI] RV730 GL [FirePro V3750] Kernel driver in use: radeon