I built this system around two and a half years ago with a Core i7-13700K, Z790 Hero motherboard, RTX 4090, 64GB of DDR5-6400, multiple NVMe drives, a 360mm-class liquid cooler, and a 1000W power supply. I previously set an 80°C CPU temperature limit and applied a light undervolt, but the system has always seemed stable and stays cool.
My main problem is Farming Simulator 25. The game appears to be limited by one or two CPU threads, while the RTX 4090 remains mostly idle. At 3440x1440, performance can fall below 30 FPS around my farm, even after lowering view distance, shadows, traffic, and other settings. Frame generation is sometimes necessary, but panning still feels sluggish.
I initially thought my processor was defective because Cinebench reported only around 6,300–6,400 points in the multicore test, with a single-core score near 674. I later realized I had been using the wrong Cinebench version. After running the correct test, the processor scored roughly 30,000 points, even with other applications open, so the CPU benchmark itself appears normal.
In-game monitoring shows temperatures around 43–55°C. Most cores remain lightly loaded, while one or two fluctuate in the 60–70% range. GPU usage is also low, and CapFrameX reported about 35% GPU usage at 24 FPS. I have updated the BIOS and drivers and would prefer not to remove the 80°C thermal limit. What should I check next, and is this mostly a limitation of the game's engine or are there settings that could improve performance?
3 Answers
The corrected Cinebench result suggests the CPU and cooling are working normally. A single-threaded game will not necessarily show 100% overall CPU usage: one fully busy thread is only a small percentage of a 16-core/24-thread processor, and the game may split its workload between a couple of threads. Check per-core effective clocks in HWiNFO rather than total CPU usage, and use CapFrameX or PresentMon to compare frame time, GPU busy time, and CPU busy time.
If GPU busy time stays low while one game thread is consistently the limiting factor, the bottleneck is the game engine rather than the RTX 4090. Draw distance, shadows, reflections, traffic, AI activity, production buildings, and large maps can all increase the main-thread workload. Test in the same location with those settings changed one at a time. A large, heavily developed map with automation running can be much more demanding than an empty field, even when the graphics settings are low.
CapFrameX's GPU percentage is the important clue here. Around 35% GPU busy at 24 FPS means the graphics card is waiting for the CPU or the game engine, not struggling to render the scene. Low overall CPU usage does not contradict that because the main thread can be blocked on synchronization, streaming, simulation, or other engine work without making an entire core read as 100% continuously.
Try a clean comparison on a small default map with traffic, Courseplay, AutoDrive, productions, and background applications disabled. If performance improves there but collapses on the developed 16x map, the map and simulation workload are the likely cause. Also verify that the game is using the intended power plan and that per-core effective clocks remain high during a hitch, but there is no obvious reason to remove the temperature limit when the CPU is staying in the 40s and 50s.
The original 6,300-point result would have indicated a serious configuration or throttling problem, but the corrected result changes the diagnosis completely. I would leave the 80°C limit in place. Since your temperatures and Cinebench score are normal, raising the limit is unlikely to fix a game that is bottlenecked by an older or poorly threaded engine. Focus on frame-time captures and comparing different saves or maps rather than chasing multicore benchmark numbers.
That matches what I am seeing. The benchmark reaches about 30,000 now, but the game still has one or two cores fluctuating in the upper 60s and 70s while the GPU sits well below full load. Lowering the usual graphics options has made surprisingly little difference, especially on the large map.