For gaming performance, we tested each motherboard using the GeForce GTX 780. The card was tested in each available PCI Express x16 slot to measure how much impact the varying bandwidths had on frames per second performance.
The Gigabyte Z97X-SOC Force was able to push the GTX 780 to its limits in the first, second and third PCIe slots. The fourth slot saw a 6% reduction in performance compared to the first. Meanwhile, the Asrock Z97X Killer, which has three PCIe slots, provided strong performance in all of them.
The Asrock Z97 Extreme6 works best with two-way setups as only the first and second slots allowed for maximum performance. The third PCIe slot was down 13% on performance compared to the first.
Again, we see similar margins in Tomb Raider as we did when testing with Hitman. The Asrock Z97X Killer works well with three-way setups as does the Gigabyte Z97X-SOC Force. The Z97X-SOC Force takes a slight hit on the fourth PCIe slot, dropping a few frames per second.
The BioShock Infinite results are interesting. The Gigabyte Z97X-SOC Force pushed the GTX 780 to its limits in the first, second and third slots while the fourth was 7% slower. The Asrock Z97 Extreme6 provided maximum performance on slots one and two while the third was 15% slower.
The Thief benchmark showed a huge drop in performance for the Asrock Z97 Extreme6 when testing the third PCIe x16 slot. This slot was 28% slower than the first and second, obviously a significant reduction.
For the first time, the third slot on the Asrock Z97X Killer was 5% slower than the first, while the fourth slot of the Gigabyte Z97X-SOC Force was 17% slower than the first.