PCI Express Scaling Game Performance Analysis review - Performance - 2-way SLI GPU - Alien Isolation

GeForce GTX 980 2-way SLI DX11: Alien Isolation

We now move onwards to GeForce GTX 980 in 2-way SLI. We'll again perform our regular average FPS test and then fire off FCAT to check out and see if there is any relation in-between the dated PCIE Gen 1.1, the modern PCIE Gen 2.0 and then the latest PCIE Gen 3.0

Above the results at the best image quality settings. We will be testing at 2560x1440 (WHQD), we in fact do this with all titles as we want to emulate the way you game at home as close as possible. The result differential with SLI is far more substantial as we are stressing that PCIE slot more. Now I can't believe for a second that you would run high-end SLI with that outdated PCIe Gen 1.1 slot, but the performance is definitely worse. Compared in-between PCIe Gen 2.0 and 3.0 the difference is much smaller in the 5% and we can back that up with what we measured with the internal benchmark with FCAT.

• Grey line - GTX 980 @ x16 Gen 1.1
• Dark green line - GTX 980 @ x16 Gen 2.0
• Light green line - GTX 980 @ x16 Gen 3.0

So the upper chart is an FCAT FPS percentile chart showing the percentage of frames relative to FPS rendered in a one recording. You can see that the grey line (PCIE Gen 1.1 x16) is now a good notch slower opposed to gen 3.0 @ x16.

Once we spread out a recording of almost one minute and overlay latency results (lower latency - better) we can see a hint better as to what you are seeing on screen. Since we manually have to start-up the recording, the start and thus end of the recording can be shifted a bit. But hey Gen 1.1 is grey and is showing higher latency and thus is higher up in the graph. the lime green is Gen 3.0, it has lower latency and this sits lower in the graph.