The Core i3 processors are an interesting product when it comes to heavily multi-threaded performance in applications like 3D rendering or media en/decoding. On the one hand, the dual-core nature of the Core i3 processors puts them at a disadvantage against quad-core processors. However, Intel has left hyper-threading enabled as a means of combating this disadvantage.
The effectiveness of hyper-threading seems to be mixed. Most benchmark results show that the Core i3 processors perform quite a bit better than older Core 2 based processors like the E7600. In fact, the Core i3 processors are often faster than the Core 2 Duo E8400 and E8600 in heavily multi-threaded applications, and by no small margain. This shows that hyper-threading is doing its job.
The problem, however, is again the AMD Athlon X4 630. The Athlon X4 630 has four physical cores, and this gives it an advantage. In some Cinebench benchmarks the X4 630 is 25% quicker than the Core i3-540. This is not a result which is repeated in every benchmark, but there are few instances where the Core i3-540 is quicker.
Again, the problem comes down to price. The Core i3-530 and Core i3-540 are simply too expensive when compared to the X4 630.