I have an Intel Core 2 duo E6850 and a GT 610 and reach minecraft at lowest settings maybe 200 fps and a type of graphics card with the same settings has reached 375 fps… Since I have the feeling that my CPU slows down the GPU
Your PC slows everything down.
Whether CPU or GPU.
The whole pc is not meant to gamble.
If you really want to know, the GPU is worse than the cpu, but both are very old and can't be compared to today's hardware.
If you're thinking about upgrading I'd rather advise you to a new PC.
Does he have the same hard drive? Do you have the same board? The same RAM?
There are other factors than just the CPU and the Graka.
8gb RAM motherboard I have no idea
Is it the same RAM?
Otherwise, there are of course software that can be different. Just the settings in Windows can make significant differences.
Comparing the pure hardware will not be enough.
8GB Ram are also a bit small.