Ok, you have a couple different questions in here, somewhate nested inside questions.
Would it be possable to get a 7900 GTX in there??
No, unfortunately the 7900 class cards are extrememly big, they have huge heat sinks, and they simply won't fit in a case this size (right now - maybe in the future with liquid metal cooling, and a smaller manufacturing process or something like that, but right now, no.)
Which performs better Intel Core Duo or the AMD Turion X2 Dual Core?
THAT, is the $64,000 question, isn't it?
The simple answer is the
AMD Turion X2 (hereafter (TuX2) is faster than the Core Duo.
The
Intel Core
2 Duo (hereafter; C2D), is
mostly faster than the TuX2.
BUT, here is the thing, the Core 2 Duo is almost
too powerful, what does that mean?
Well, I have found with my benchmarks that for gaming, the C2D doesn't do
much more than a Core Duo if you have less than a 7800 class GPU. Turns out that the GPU is the bottleneck in the system.
The TuX2 on the other hand, in the 7600/x1600 class of GPU's performs better
for gaming. Now this is pure numbers talking. To me, when I watch a game demo like "
Return to Proxycon" in 3DMark 05 or 06 the TuX2 is smoother than the Core Duo. It is about the same as the Core 2 Duo. You get some better frame rates, which makes sense since the AMD platform was pretty much custom tailored to gamers.
The memory is better handled with the TuX2 of course because of the onboard memory controller, I think the GPU has a slight edge (pretty game specific) as far as future proof-ed-ness (?).
For regular work and apps, you aren't going to notice a difference, and since the C2D finally came around to 64 bit, the playing filed is much more leveled. If, again we are talking baout the standard Core Duo, then you have to hand it to the TuX2 here again too, being 64 bit and the Core Duo being 32 bit.
Contrary to what a lot of people are saying about 64 bit O.S. and the negligible speed difference, I can tell you with 100% certainty, there is a noticable performance improvement, even on 32 bit apps. It is overall faster, I have used it, I can tell the difference when something is faster, and when I don't have to look for it, it is definately there.
There was an article on Tom's saying that the Turion X2 was pretty much too little too late and a "
second choice"... if that. That is just silly, and so vague and generalized that it just might be arguably true in a pure numbers sense, but in reality like all things, it is true within a certain band of performance, which is being focused on.
To say that
"[compared to the C2D] the Turion X2 is too little too late, and a second choice... if that" Is like saying, "
In Japan, the hand is used as a knife. In Japan a man wife's hand job then can cost him his life." Kind of two differnt applications, you know? Everything in the world is tuned to operate optimally within this "specific performance band". A dragster has more horsepower and is
faster than a Triumph 995i Daytona SuperBike... in a straight line... but it is difficult to compare the machines by horsepower without looking at the other factors, making it difficult to compare the two in any other way.
You simply can not compare a decked out T7600 2.33 Core 2 Duo in an Executioner with a 7900 GTX with 512 Mb of GDDR3 to a TL-60 2.0 Ghz Turion X2, nVidia 7600 256 MB in the Zatoichi,
all other things are
not equal. It is the
other things that make that
ultra-high-end machine kick-ass throughout its performance band. The more money you spend, the wider the performance band can be made. For what you want to do, and what you want to spend, it would be difficult to beat the TuX2 IMHO.
I personally love this computer... maybe because I have a soft spot for
AMD, but mostly I think, because the thing is awesome, and for a sub-$2,000 machine ($1999
fully loaded, it can't be beat. When we look at the "
performance band" of mid-level GPU's (x1600/7600) and
less than $2,000 then you are looking at the hands down winner.