lag issue

Normally when I play beamng, i get 40-60 fps on all maps.except maps which ae too big and crash.
When i play too long even though i have a cooling pad, The game suddenly lags with 1 fps, and kicks me to the lock screen. It lasts for a bit, and then the game is still there, but 15 to 20 fps on all maps. Its like that when i play for a certain amount of time, then lag 15-20 fps, then 40-50fps, so on. Even if i spawn on grid map i get 30fps with 1 car in the lag period, and 80 fps(very rarely) on the grid map with 1 car.
Pc specs: i5-1235U
8GB of ram
Iris Xe gpu
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i have cleared cache as well

 

When in BeamNG, you should press Ctrl + Shift + F to open a more detailed performance graph.

There will be a line of text with different components. (see image below) If any of them are flashing red, they indicate a bottle-neck. If for example, the CPU text is flashing red, this means your CPU is bottle-necking.

Have you ran the game in safe mode? Or with the Vulkan renderer?

 

vulkan doesnt work. it says cant find something
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safe mode: laggy at first 15fps spike, then 30 to 40 fps