I really need Help in my PC :/

My guess would be that the CPU or GPU get to hot and change to a lower frequency.
Have you cleaned the MaxBook since 2010? There is dust in there for sure, so the cooling won't work as well as 7 years ago.

There's still a lot of possibilities... did you check if there's any background tasks cluttering up your resources? If you haven't, try to check stuff like that first, e.g. RAM usage, weird CPU/GPU spikes, page file, bad HDD, driver issues etc.

I'd suggest starting with a compressed can of air and dusting it.
Also, Macbooks look trendy and slim and all that, but in exchange they are more cramped than most anything else. So overheating will always be a problem if you try to play something more demanding on them. So you may just experience something normal for them.

old hardware and not original software ... no idea how well that runs, what i can tell is if the HDD / Hard Drive has never been replaced its garbage tier hardware about to die in the next 2 years of use or to be slowed down to crippling speeds that make it unusable

best try and bench / check your the hard drive's speed / approximated health with any of these tools:

• HD Tune
• crystaldiskmark & crystaldiskinfo
• plenty of other tools ...

if it was replaced or moderately used > a well functioning SATA3 2.5" 5400rpm hdd form 2010 would be around
(sequential) ~ 65MB/s read / 45MB/s write - if its much less than that, then chances are that is the problem

Fan problems can cause it, if you also hear strange and ugly noises right now or in the future then it's from the fans.

Does that particular laptop have a dual GPU, one integrated and one external? If so, then it could be auto-switching between the integrated and the external and that may be causing the problem. If you force it to only use one of the GPUs, the problem may go away.

After doing some checking, the one thing that seems to work for other people that had this problem is to reset the SMC:

https://support.apple.com/en-us/HT201295

http://osxdaily.com/2010/03/24/when-and-how-to-reset-your-mac-system-management-controller-smc/

Give it a try.

It probably wouldn't hurt to reset the PRAM (NVRAM) as well:

https://support.apple.com/en-us/HT204063

http://osxdaily.com/2010/11/15/reset-pram-mac/

Let me know how it all goes and whether things are working better after you do both.

Go to an apple store, and ask the experts.

I don't know the exact solution, but if nothing else is working and you have a spinning (not solid-state) HD for your main storage, the motors could also be dying or the platter could be running off-center because of drops or impacts and such. I've also seen similar symptoms from faulty ram, though that's more likely to just give you constant random prog crashes. Check for errors and fragmentation on the HD if you haven't.

I've always run Win XP and recently started using Win 7. I have noticed in 7 that "Aero" sometimes causes problems where my games will start to stutter and then even if I close the game, the Windows desktop and anything else I do will also feel laggy and stutter. Windows Aero is basically vsync for your desktop and allows some special visuals to work, like the transparent "glass" effect on the windows titlebars.

I often have to disable and re-enable Aero to fix the problem and some games need it turned off to play properly. It is safe to turn it off, it only disables some visual features and vsync for your desktop. You can easily turn it back on, or if you just stop the service how I explain here, it will automatically turn itself back on the next time you restart the computer.

• In the start menu, use the search bar or "run" if you have it enabled and open services.msc. That will bring up a window that shows all the services for Windows.
• Scroll down to "Desktop Window Manager Session Manager".
• Right click on that and click "stop" or you can open it's properties window and click stop.

That is all, see if that helps in the game. If you want to restart the service, just open services.msc again and click start on that service or restart your computer. If you open the properties window for that service and change the startup type to disabled, that will disable the service permanently so that it does not start with Windows and will not start again until you change that setting back to automatic.

Also, this setting turns on vsync for your desktop which means vsync will be enabled in windowed and borderless windowed games, which may introduce input lag and you may want to disable it when you play those games. True full screen games should disable it automatically.

This may not have anything to do with your problem, but it's worth a try. It only takes a few seconds and can't hurt anything.