OK so these cards DO work CFXed in a Sabertooth R2 so at this point I'm going to blame the Crosshair or the OS as I'm running out of options here. The only thing I could suggest is trying CFX using Windows 7 32-Bit just to rule out an OS issue.
Can anyone else chime in here...is there some hardware glitch here or something obvious we are missing?
Also if I remember right your Sabertooth R2 supports PCI 3.0 where the Crosshair supports PCI 2.0 This (PCIe 3.0) is accomplished by adding a PCI 3.0 bridge that in connected to the Northbridge which is maybe "why" these cards CFXed in the Crosshair do not function.
I just don't have a lot of experience in working with CFX/SLI to be of much help here; sorry
🙂 Maybe you can attempt to find one of the Asus Reps that post from time to time in this forum to see if they can provide any insight or offer advice?
Keep us posted with your progress....hate to lose one to the dark side (Intel)
🙂
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For trouble-shooting tips see my blog at:
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http://thenerdbench.blogspot.com/p/bench-testing.html
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MB: Crosshair V Formula-Z • CPU: FX-8350 • GPU: Asus Matrix R9 280x • RAM: 8GB of Crucial Ballistix Tactical Tracer (1866)• PSU: Thermaltake DPS Thoughpower 750 Watt • CPU Cooler: Thermaltake Frio Advanced • Keyboard: TT Sports Challanger Ultimate • Mouse: TT Sports Black Element • Case: Thermaltake GT Level 10
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