Question: After installing two R9 295x2 VGA cards on my X99 platform, the system fails to boot up. How do I fix this?(3/1/2015) Answer: Please refer to the following steps to update the BIOS from ASRock's website.
X99 OC Formula
Step 1. Please remove all unnecessary PCI-E devices including 1 R9 295x2 VGA card, and only install one VGA card onto the system as a display output.
Step 2. Boot up the system and then enter into BIOS setup.
Step 3. Please load the BIOS default settings and then save the settings.
Step 4. Enter into BIOS setup and choose "Instant Flash" to upgrade to the latest BIOS
Step 5. After successfully updating the BIOS, please install the second R9 295x2 VGA card onto your system.