While Trying to setup Dell R720 with NVIDIA Grid K2 for XenServer 6.2 SP1 It may happen that after you install the nvidia driver and reboot the server , the module for nvidia is not recognized . To verify the install after reboot you may run the following command lsmod | grep nvidia If it does not find any module then we may have to disable one setting in System BIOS for Dell R720 server. This is the setting you need to disable. (Memory Mapped I/O above 4GB) You can find it Under > System BIOS > Integrated Devices > After the server come back online , you can run the following command to verify the module was loaded fine lsmod | grep nvidia The output should be something like nvidia 9626462 26 i2c_core 20294 1 nvidia Verify that the NVIDIA kernel driver can successfully communicate with the GRID physical GPUs in your system by running the nvidia-smi command. The output should look like: +---------------------------