Three questions I always ask myself vis-à-vis benchmarking or so-called top-ten lists of anything:
1. On what kind of setup was the component tested;
2. How was the component put through its paces;
3. What does all of this matter to me and my intended application?
Very true.
Using graphic card benchmarks as a reference:
The FPS results of CARD A may make you go 'wow' - until you realise that the base test system is some highly overclocked beast in which you would never achieve similar results in
your own machine with the same CARD A.
Settings such as drivers, resolutions, xAnti-Aliasing, xAnisotropic Filtering etc used also have a big impact on results.
You have to base your judgment on what comes
the closest to your machine specs and intended usage.
It's also similar to synthetic CPU/RAM tests. Often that big 'wow' number equates to no discernible difference in 'real world usage'.
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I've glossed through the thread, so forgive me if this question has been asked:
What is the
Primary intended use for this new machine?
► Pure gaming, good all rounder etc?
► And how long do you plan to use this machine before another complete upgrade?
► Down the track, do you ever plan to run a multiple GPU set up? (Crossfire/SLI)
► Down the track, (once researched a little more

) do you plan to ever overclock?
Either way, A 4 core should be a realistic minimum for 'longevity'. DDR3 for ram and a motherboard with USB 3.0 and SATA III. (The latter is if you are planning to planning to keep the machine for several years)
As it's already been pointed out, more and more applications and games are starting to benefit from the extra cores. Dual core CPU's are starting to show their limitations.
AMD / AM3 = Great selection of mobos + wider range of compatible CPU's.
More 'upgrade path' options depending on chosen motherboard. ie an AMD Phenom II 955 overclocks well but can still be replaced by the new hexa-cores.
Intel 775 = Essentially End of Life, but a Q9xx + DDR3 + CARD X will still deliver good gaming/desktop performance. However, since it's E.O.L, I'd personally rule out a 775 based system.
Intel 1156 = Great selection of boards, but virtually non-existent upgrade path as it also already superseded.
However an OC'ed 750 will still give great performance for gaming/desktop usage.
However, one limitation here is that the P55 chipset does not allow for for full x16/x16 of crossfired/SLI'ed cards. This is not a real big issue for current gen cards, but will become one in times to come.
Intel 1366 = Again, great selection of mobos', but also already superseded. The only real 'upgrade option' is intels hexacore, the the i7 980x (and rumored 970).
However the 1366 socket set up is not bang for buck.
Realistically, the 'bang for buck field' is either a choice between an AMD/AM3 based socket, or an intel 1156 based socket. Both setups will still be quite uesfull for several years yet.
TBH, all the above sockets are already out-dated - but waiting another X of months is never ending process.
At this stage, the video card choice should not be that important.
There are plenty of cheap and decent cards currently available from both camps that will suffice until the next ATI/NVIDIA release. Even if you don't buy one of the 'new cards' - the price will drop on current 'flagship' cards.