Dell Inspiron 5593 Thermal Throttling

I bought a Dell Inspiron 5593 Core i7 laptop few months ago. CPU throttles down to 0.34GHz when the dedicated GPU(MX230) starts to work. It makes my video editing experience worst. I've done some testing. Cinebench R20 benchmark predicts that there's no problem with the CPU. But when I run Heaven Benchmark 4.0(When MX230 comes into play), CPU throttles down to 0.34Ghz. Benchmark results were worst. I've checked the CPU and GPU temperatures. While Heaven Benchmark 4.0 was running, CPU temps were around 80C and GPU temps were around 75C. These temps predict that there's not much of a problem with the temperatures considering that both 1065G7 and MX230 can reach up to 100C. I've tried doing lot of things. I even contacted Dell support before and the assistant couldn't give me a proper solution. I've tried undervolting CPU, didn't work. Ran both intel and dell diagnostic tests, both predicted that nothing is wrong. Tried doing thousands of things. Nothing resolved the issue. Currently, I'm using my laptop with MX230 disabled. Gaming, video editing both on intel iris plus g7 graphics. I'm hoping anyone in the community or dell tech support or else a BIOS update could help me to resolve this as fast as possible.