Originally Posted by filburt
I am a bit confused by the product matrix, mainly for 27" model.
There are 4 variations, 2 regular, 2 built to order CPU upgrades:
- $1699: 3.2 GHz i3 (dual, hyper-threading, 4 MB L3), ATI 5670 512 MB
- $1899: 3.6 GHz i5 (dual, hyper-threading, 4 MB L3), ATI 5670 512 MB
- $1999: 2.8 GHz i5 (quad, no hyper-threading, 8 MB L3), ATI 5750 1 GB
- $2199: 2.93 GHz i7 (quad, hyper-threading, 8 MB L3), ATI 5750 1 GB
Now, I realize 5750 is a better GPU than 5670 (AnandTech's review
shows around 10 fps improvement across the board) and having double the L3 and true quad may possibly outweigh faster clock on BTO $1899 iMac. But it is a confusing matrix nevertheless. I wish someone were to compare them head on.
I think your choices are simpler than you think.
Synthetic benchmarks are difficult to use in this situation, because a 3.6GHZ dual core could outperform a 2.8GHZ quad core, in applications which are not very efficiently multi-threaded.
On the PC side, Anandtech and Tom's Hardware have done tons of benches comparing high-clocked duals with lower-clocked quads.
Bottom line IMO is, 2.8GHZ quad (even with no hyper threading) will be a better long-term investment (say, 3 years) for all-round performance. However if you use specific, single apps that you know really fly on dual cores and not quad cores, and you will be hammering the CPU hard with these apps over the next year, then the 3.6GHZ dual is the machine for you.
This one's easy. Either you play games on the Mac, use OpenGL 3D software, or you don't. If you do, accept nothing less than the 5750 1GB. Driving the native 27" resolution, even the 5750 1GB will struggle at modern games. You probably have to turn it down to 1920x1080, but you'll play modern games at very high settings at this resolution with the 5750 1GB. Don't let the 10fps fool you, the 5670 512MB is a much cut down architecture from the 5750, which is cut down from the superb 5800 series.
I would propose as follows:
$1699: 3.2 GHz i3 (dual, hyper-threading, 4 MB L3), ATI 5670 512 MB
For those that want the 27", who don't have too much video, audio or gaming needs.
$1899: 3.6 GHz i5 (dual, hyper-threading, 4 MB L3), ATI 5670 512 MB
For those that want strong performing dual-core-optimised applications which do not take real advantage of four cores, and for those without significant gaming needs.
$1999: 2.8 GHz i5 (quad, no hyper-threading, 8 MB L3), ATI 5750 1 GB
The "sweet spot" ~ future-proof CPU performance for all round video, audio and gaming needs.
$2199: 2.93 GHz i7 (quad, hyper-threading, 8 MB L3), ATI 5750 1 GB
The "best" ~ for those who just don't give a f*** and want the best iMac money can buy, who can overlook the insane price for a system with a GPU of that class. Seriously though, also this would be for those who run well-multi-threaded applications most of the time, with average gaming needs.