1. is it safe? considering i only got the base cooler and the pc runs almost 15-20 hours per day
My CAD workstation runs an E8500 at 3.8GHz. It runs 24/7 and has done so for 2.5 years straight.
If you don't overvolt your CPU with crazy amounts of overclock, and you don't run it too hot, it will not harm it. You will not know how hot it will run until you try it, especially with the stock cooler.
1. The only way to determin if its safe is to work your way up to that point and see if it becomes unstable. Not all CPU will oc the same.
2. Raising the freq will help with game performance if that is what you are asking but only to a certain degree.
Overclocking your GPU will show much more improvement in gaming compared to the cpu but ocing both will help a ton. Just know your limits and take baby steps. (sometimes its better to oc the cpu if its causing a bottleneck on the gpu.) It all depends on what you have in your system and what you play on it.
Slow and steady wins the oc race and keeps your components alive.
I would suggest buying a HSF like the Scythe Mugen or Hyper 212 so it will run cooler which will allow you to oc it more.
those hsf are at ~ 70 dollars here
i dont wanna invest in hsf for such a weak cpu though, cause if i do, i will have to buy a new computer with new pieces and thats not what i want atm
i got ati 5670 gddr3 1gb, i can OC it for <100 mhz more
is that the OC u meant about the GPU?
i want to play things like crysis and gears of war with maximum details on 1280x1024
i will have 4 gb of ddr2 800 mhz, gpu 5670, cpu e7200
i have never overcloacked a pc component before, thats why i dont want to change voltage and stuff like
i heard that i can change the speed of the cpu from the bios to about 3ghz, thats what i m looking for