I'm planning to build a gaming pc for around 700- 750 $.... im very confused with the processors and graphics... i've got only two options due to budget constrains....plz help.
Try this, got you up to a 7870Ghz edition with Windows 8 64 bit. just under $700. Might be able to get away with getting a 7950 or maybe a Vishera CPU (FX6300) if you are willing to go to the $750 mark. You will have to find a optical drive. hopefully you have an old PC lying around with one you can part out.
Wait a little and see how much the new Radeon HD 7790 is.
Its ment to be better performance than the GTX 650 Ti (we will see)
If you go for the fx 6 core see if you can get the 6300 (i have the fx 6100 and my old Phenom II X4 965 - 3.4 Ghz seamed to be much faster in games and pulled a better windows score)
I'm with cooperman - if you are going to fork out for a six core AMD, then go with the Piledriver if possible (FX-6300). The AMD option you suggested seems like the way to go, it leaves you more money for a better GPU which is what matters in gaming.
My old rig was a Phenom II x2 555 BE with a mild overclock, and paired with a decent card (GTX560Ti) there wasn't much I couldn't run at high or ultra at 1080p over the couple of years I had it in operation.
AMD is centainly trustworthy they have no problems with overheating or power consumption for me at least those are myths. Maybe those were true a long time ago but the last couple of years AMD has been pretty much on par with intel and they are even doing a lot better then intel in some ways.
Also if you do have currently do have an old rig someone mentioned re-using the optical drive to save some money, check what PSU you have if you can re-use that you'll save even more money.
Forte has some good advice there - cannibalise whatever you can from other rigs that are laying around.The PSU and optical drive from another rig will definitely save you money.
As this is for gaming I would even go as far as to recommend that you use an HDD from an old rig and forgo an SSD if you are planning to get one. That will free up money for a better CPU GPU combination - trust me, a better CPU and GPU with a crummy old 5400rpm SATA II HDD will be much better in gaming than a cheaper CPU GPU combo with an SSD.
Indeed you might as well keep everything the same (unless you need a better PSU or bigger case to fit everything inside of it) and upgrade the mobo, CPU, GPU and if possible the RAM(you shouldn't ever have to throw away RAM unless you are updating from DDR2 to DDR3 or if you already filled all the slots and want more RAM in which case you'd need to get a couple of new sticks and get rid of a couple of old ones)
Also if your current RAM is too slow you will hardly notice a difference in faster RAM, if you still want it to be faster overclock the RAM (going to cost you $0) and buy new/faster RAM if disaster strikes and the sticks die which is unlikely unless you go crazy with the overclock.
I upgraded pretty much every part of my PC in the last 3 years, only things that are left unchanged is the mobo, CPU and GPU, upgraded the RAM and added HDDs/SSD but didn't have to get rid of the old RAM/HDD.
I think the closest I will come to getting a "new rig" will be the mobo/cpu upgrade (and maybe RAM if I decide to wait for DDR4)