ASRock Forums : Problem with 280X Crossfire on 2 mobos

Problem with 280X Crossfire on 2 mobos : I was going to say that based...

Mon, 08 Jun 2015 13:46:33 +0000

Author: Xaltar
Subject: 228
Posted: 08 Jun 2015 at 1:46pm

I was going to say that based on the manufacturers of your GPUs they should work together until I saw the Sapphire card is a Vaptor X model. Powercolor and Sapphire both typically use reference design boards in their products however, the Vaptor X series use non reference board designs and a tweaked bios. While technically they should still work together with the system defaulting the clocks to the lowest of the two I suspect that the Vaptor X may not be playing nice with the powercolor card.

Given that you have tried 2 separate motherboards with the cards that is where my suspicions lie. Should this be the case you will need to trade in or sell then buy one of the cards to get two matching cards. I would try and get another Vaptor X as they have better cooling and board designs.

Problem with 280X Crossfire on 2 mobos : Intel CPUs like yours provide...

Mon, 08 Jun 2015 12:27:05 +0000

Author: parsec
Subject: 228
Posted: 08 Jun 2015 at 12:27pm

Intel CPUs like yours provide 16 PCIe 3.0 lanes, which are used with the video card slots.

As is normal for any board with a CPU like yours, when two of the PCIe x16 slots are used, they run in x8/x8 mode.

That should be fine for Crossfire, since it only requires at least an x4 connection for the second card. Two AMD cards can be used in Crossfire in x8/x8 mode.

The Z75 Pro board had the second x16 slot connected to four of the PCIe 2.0 lanes in the Z75 chipset, and that board supports Crossfire too.

The AMD/ATI Crossfire driver requires that the Microsoft software package, Microsoft .NET Framework is installed in the PC before the Crossfire driver is installed.

Your Z77 Extreme4 board's manual has instructions for installing the Crossfire driver and video cards. I strongly suggest you read that, it is not long but has essential information.

What worries me is the two different manufactures of the video cards. Yes they are the same basic model, R9 280X with the same memory capacity and interface, but the VBIOS (Video BIOS) of each card seems to be slightly different, and they seem to not be happy working together in Crossfire.

I suggest asking about this in the AMD video forum, and/or PowerColor and Sapphire forums, about mixing different manufactures cards in Crossfire.

Problem with 280X Crossfire on 2 mobos : So for the past 3 months ive been...

Fri, 05 Jun 2015 22:49:41 +0000

Author: Wreekhavok
Subject: 228
Posted: 05 Jun 2015 at 10:49pm

So for the past 3 months ive been slowly upgrading my rig apiece at a time.

My current specs are:
ASRock Z77 Extreme4
I7 3770
8gb of DDR3 RAM
Sentey 1000w 80plus Bronze Modular Power supply
1x PowerColor TurboDuo AXR9 280X 3GBD5-T2DHE/OC Radeon R9 280X 3GB 384-BitGDDR5 PCI Express 3.0 HDCP
1 x SAPPHIRE Vapor-X 100363VX-3L Radeon R9 280X 3GB 384-Bit GDDR5 PCIExpress 3.0 CrossFireX Support TRI-X WITH BOOST

This issue im running into is When I connect both videocards and power on the system, it gets to the ASRock screen and power cycles.It just keeps doing it, I can only get into the UEFI BIOS and no matter whatsettings I change it will not boot to Windows.

Both cards are recognized in the UEFI system manager. Primarygraphics is set to PCI-Express. PCIE2and 3 are set to AUTO. VT-D is enabled, I even tried raising the VTT voltage toover 1.2 and still no difference. The crossfire bridge is connected.

I originally had at Z75 Pro3 and replaced it because of thesame issue. I thought not having 2 PCI-E x16 slots was the issue, but now Ijust don?�t know.

Both cards work when I only have one installed, in bothPCIE2 and PCIE3 slots.

I have also installed both cards and left one unpowereduntil Windows boots and then connected the power and the card works fine butwill not show up in the hardware manager.

I have uninstalled CCC and reinstalled multiple times, Ihave installed every driver I possible from the ASRock site for each mobo andstill no luck.