Which intel CPU would the AMD FX-6300 be equivalent to?

Solution
It's direct competition is an i3. It has to be overclocked to soundly beat an i3. FX 6350 speeds will beat an i3 3225. It takes a bit more to beat an i3 4150. I don't consider the 4130 anymore since the 4150 is a little less right now.
According to Toms these are all tier3 processors

Core i7-860, -920, -930, -940, -950
Core i5-3220T, -750, -760, -2405S, -2400S
Core 2 Extreme QX9775, QX9770, QX9650
Core 2 Quad Q9650
FX-8120, 6200, 6300, 4170, 4300
Phenom II X6 1075T
Phenom II X4 Black Edition 970, 965, 955
A10-6800K, 6790K, 6700, 5800K, -5700
A8-3850, -3870K, -5600K, 6600K
Athlon X4 651K, 645, 641, 640, 740, 750K
 


It really depends on the game.

In newer games that can use 6 threads the 6300 is better than even a 4th gen i3 and is more in line with the lower end i5 processors.

In games that only support 1 or 2 threads, the more powerful cores on the i3 are better.

Newer games like WatchDogs and Battlefield 4 are favoring more cores though so the AMD 6 and 8 core chips are doing better than they were.