im confusedboi

I did reinstalled the gpu after removing it from the system and for a while it gives output on the moniter but after a while being idle the output stops on the moniter and system keeps running fine but there isn't any output and also Im trying out the pop_os and installing the drivers it shows error and moniter and cables and power connectors are fine But I suspect if its gpu or the gpu socket as it works fine after removing it and reinstalling but if left idle its output shuts but the system keeps working only the output from gpu.

Hello I've a very old gpu regardless it works but after booting onto the desktop screen if left idle montor doesn't output even tried to press keys to see if it in sleep mode but no use and will only display output after removing the gpu from the system and reinstalling it. So,whats the problem here and any help is appreciated!

Thanks! and yeah totally forgot to mention my psu is 600 watts and well Im getting a new case this week!

i think Im not gonna go above the rtx 2060 or its super variant and for the time being what should I upgrade first gpu or the cpu I can wait for ryzen 3000 Appreciate it man!

current system specs: cpu-pentium g3220@3.00ghz ram-4gb ddr3 ram mobo-gigabyte h81-M gaming 3 lga 1150 gpu-hd 4350 Im thinking bout ryzen 3000 series for cpu upgrade/system or a vega 56 or rtx 2060 for a gpu upgrade so what should i upgrade?