Hello there.
I recently bought a used PC with the following specs:
I5 750 2.6GHz
Radeon HD 5750 1GB
8GB Corsair Vengeance RAM
Gigabyte P55-USB3 motherboard
Corsair GS600 PSU
Antec Case (I think it's a 203)
I noticed that the system was very slow and even turned off twice, so I downloaded Core...