Firstly, if your pc is running slowly or is performing bad due excessive files & programs then do some house cleaning and remove that unnecessary load. Remove temporary internet files, old ,exe programs, etc.
I also suggest getting yourself an external hard drive, 500G & 1000G are extremely cheap now, and place the majority of your files that you do not use on a daily basis there.
Besides storing a large portion of your files, make a separate folder and use it for system backups.
As well, defragment your system after doing so..
You should notice an improved difference on your computers speed.

Now onto being more productive with your time...
Besides being in a comfortable chair, have a few snacks and water nearby to increase your energy.
Secondly, as a rule unless I am underway with my laptop... Always work with dual (2) monitors!
The cost of investing in a new graphic card and monitor is really nothing in comparison to the increase in your productivity.
If you are well busy with different message windows during the course of the day then I would even suggest adding a third monitor as I have done at the office.

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