A10-5800 VS G860+HD6670

G860+6670 all the way. It's more powerful than the A10.

no its not. an A10 with integrated graphics have pretty much the same gaming performance as a G860+6670
however if you instead opt for G860+7750 then yes this setup will pull 25-30% better frame rates.
i strongly recommend 7750 with G860 as a great budget gaming setup.
but the A10 with a 6670 in crossfire will match G860+ 7750 is games that do support crossfire and provide good scaling so decide accordingly

According to Tom's charts the Radeon 7660D inside the A10 is weaker than the Radeon 6670 and the Pentium is also faster according to Tom's as far as gaming is concerned.

A10 + 6670 will smoke em both...

What are you using the PC for? HTPC, gaming, web browsing / videos?

There's other things to consider. Trinity scales better with higher RAM speed. Overclocking won't really be possible on the A10 without spending an additional $30 for a HSF.

Monitor resolution also has a lot to do with it.

Ok, but what if this is NOT exclusively for gaming? What if the only games will be 2D or much older titles, and the focus will be on general use, HTPC, and other media manipulation?
OP, please clarify your intended uses for this machine.

g860+6670 is just slightly (5-10% in average) more powerful than 7660D, if not same performance

however g860 + 7750/7770/7850/650ti etc can be a very capable budget combo and those will be much better than amd a10 5800k alone

i agree with u

I'm using pc for work, web browsing, games... a bit of all...

The Pentium G860+graphics card is a better choice because you have the option to upgrade + the better energy efficiency offered by such a solution.

If you ever think you might want to upgrade, the G860+HD6670 is the better choice. If you NEVER will (for example you're upgrading from an old P4+GMA system that has been meeting your needs), then either of these will be fine; go for the cheapest. Be especially mindful of the CPU; you can add any graphics card later, but right now there are no stronger FM2 CPUs than the A10; there are many upgrades available for the G860.