I've been benchmarking my hardware in the Shadow of Tomb Raider and have noticed that when running the in-game benchmark Afterburner shows 20-50% fewer FPS than the in-game benchmarking tool (e.g. where the in-game counter was at 90-100 FPS, Afterburner was at 60-70). I tried checking with FRAPS but it didn't work. Then tried the NVIDIA overlay and the FPS was in line with Afterburner. So I wonder why such a discrepancy and which app is correct on the FPS? Any ideas?