hey guys I just moved frome ps3 to Pc and I heard that I can play old ps2 games with an emulator. Can anyone explain me how it works? where can I download one safely?
PCSX2 is your best bet, just google it. It's a low level emulator so you'll find that you need a PS2 bios for it to work. You could legally get one from your own console (various ways to do it, with hot swapping and the likes), or go for a more *ahem* illegitimate route and torrent the bios. Either way, the emulator will work in exacty the same way and with a reasonably powerful graphics card you'll be able to play PS2 disc image backups upscaled to glorious hd.
http://www.emuparadise.me/biosfiles/bios.html
http://www.emuparadise.me/Sony_Playstation_2_ISOs/41
http://pcsx2.net/
PCSX2 doesn't use your GPU for anything but active anti-aliasing, anisotropic filtering and resolution output scaling, everything else is run by your CPU. I'd recommend going through the settings and making sure that it is using the latest DirectX mode that you have available and also that you engage multi-threading with as many threads as you have to spare (n-1. If you have a non-hyper-threaded quad core, keep one core free for system tasks.) You will also want to make sure to skim through the section of hardware fixes and make sure that the game you are emulating doesn't require one. It is also really useful if you assign the quick-save and quick-load slots to keys on your keyboard, as this makes some grind-heavy, low drop-rate games more palatable.
So guys, I have an fx6300 and an r9 270x. Will I be able to play games in hd??
definitely.
PCSX2 emulation is actually not that intensive as it used to be 8 years ago when people started writing code for it. As it uses CPU with most of the emulation, modern 4-8 core processors have zero problems running PS2 emulated games. There are a few exceptions where the PCSX2 code can't emulate some games like they were directly played on the PS2. Zone Of The Enders 1 and 2 seem to be a couple of those. They had some weird special optimizations on the PS2 that does not translate to the PCSX2 emulator in the same way.