Question I have super server 7047GR-TPRF that is with two GRID K1 cards, and after I installed Citrix XenServer 6.2 and boot to the win7 guest virtual machine, I found a yellow exclamation mark on the K1 in the windows device manager. Anything I should change in the BIOS menu to fix it? Answer In your case you need to update BIOS to 3.0 or later version and then disabled PCI above 4G decode, and configure MMCFG to 0x60000000. The options can be found at advanced->pcie/pci/pnp configuration->above 4G decoding advanced->chipset configuration->integrated IO configuration->MMCFG base Please also refer to following table for how to configure BIOS when using XenServer 6.2 with K1 or K2. The setting is effective to all X9 dual processor series motherboards. BIOS Setting one K1 two K1 three K1 four K1 Default setting Above 4G decode->disabled, MMCFG->0x60000000 Above 4G decode->disabled, MMCFG->0x30000000 Not supported one K2 two K2 three K2 four K2 Default setting Above 4G decode->enabled Above 4G decode->enabled Above 4G decode->enabled MMCFG->0x60000000 Was this FAQ helpful? YES      NO Enter Comments Below: Note: Your comments/feedback should be limited to this FAQ only. For technical support, please send an email to support@supermicro.com.  Enter your email address below if you'd like technical support staff to reply:  Please type the Captcha (no space) F C H B FAQ Stats FAQ ID Related Category / Keyword Date Posted Code 16727 Peripherals: - VGA (PCI-e) 08/05/13     Print Answer