OP, while both builds have their strengths and weakness, I believe you would be happy with either build.
The main points of difference between the two platforms would be Lower Power and Higher IPC (Intel) vs More Cores and Highly Overclockable (AMD).
At stock settings and in general, both platforms perform fairly similarly, Intel winning some, AMD others.
In many lightly threaded applications, Intel will win due to the higher IPC.
In other more demanding applications AMD will win due to a higher core count.
Austiin :
So which one would be better for gaming in the long run? Would it be better to get the FX just for its extra two cores in case games start using more cores? I'm not planning to upgrade in a long time once I put this build together, so which one would be more reliable for gaming in the future?
If I had to chose between only these two systems and I knew I would not be able to upgrade for quiet some time, I would defiantly chose the AMD FX 4100 build.
To start, with the FX build you will have four cores vs the i3's two.
While this may not give the FX an immediate edge over the i3, multi-threading is the future and in the long run you will be in a better position.
The FX is also quite overclockable where the i3's max clock speed is essentially fixed.
This will give you the option, with a little work, to increase your performance any time you feel the need for it.
Overclocked, I would expect the FX to handily beat the i3 in nearly every metric.
Keep in mind, at higher resolutions and graphical settings, the CPU becomes less important to performance.
This is because your GPU will become a bottleneck at higher settings/resolutions and it will not matter how fast information is fed to it.
Finally, I find the ASUS motherboard to be quite a bit nicer than the MSI.
The layout, build quality (especially in the cooling department) and features are just a step above.
In the end though, I believe you will be equally happy with either build.
Both are plenty fast enough for day to day usage and should be quite comparable in current games.
There is a problem with windows 7 and the FX . Windows cant see the cores as cores so it cant optimise threading so turbo boost kicks in . There is a hotfix coming presently that will increase performance by 5 -15 % depending on workload
I thought they released that hotfix in mid December and it actually decreased performance?
Yes, there was a hotfix, but it was pulled because it did decrease performance under some situations.
The real issue with Windows 7's scheduler is that it sees a Bulldozer module as a single core with hyperthreading (À la Intel).
In reality, a Bulldozer module is essentially two dedicated cores, just with some shared resources.
Now, how is this an issue you ask?
It all has to do with the CPU's turbo settings.
AMD's Turbo Core allows Windows to dynamically increase the speed of active modules beyond the base clock.
In order to determine if it has the TDP headroom available to increase performance, one of the main items that is checked is the number of active modules.
The less modules in active use, the more TDP headroom available to dynamically overclock.
Now, Windows scheduler, as it is currently implemented, is scheduling threads to cores based on Intel's hyperthreading model.
That is to say, Windows thinks that Core 0 is a 'true' core with full performance and Core 1 is a lower performing core.
This pattern is repeated for as many hyperthreaded cores exist in your CPU.
In order then to give you the best performance, Windows will schedule threads to fill alternate cores first, filling in the odd cores only when necessary.
While this works great for Intel's multi-threading model, it will never allow an AMD Bulldozer CPU to reach its highest Turbo Core setting as it forces more modules than necessary to be in operation during lightly threaded operations.
While fixing the Windows scheduler will not be a miracle cure for Bulldozers' woes, it could defiantly boost performance by allowing the CPU to Turbo faster and more often.