Updated 16 August
Benchmarks for the new iMacs are starting to appear. I'll update this post as I see new reviews that include graphics benchmarks, so check back periodically! (NOTE - due to problems with my ISP's server that's blocking some sites I've not been able to access Inside Mac Games for some weeks now, so I won't be able to include any IMG articles until that's fixed. If it's fixed... UPDATE 13 August - I now have access to IMG! It wasn't my ISP, rather IMG's server was blocking an IP range that included my ISP, but it took a long time to get sorted...)
Macworld's first look at benchmarks.
This one is very interesting. They don't yet have the 2.8GHz Core 2 Extreme to test, but Macworld included one game benchmark on the other three new iMacs - Unreal Tournament 2004. These were using the new ATI HD 2400XT/2600PRO graphics with 128MB and 256MB memory respectively, compared to the previous 24" 2.16GHz with GeForce 7300GT 128MB graphics.
NONE of the three new iMacs tested could match the 2.16GHz Core 2 Duo with the GeForce 7300GT - even though the 7300GT was only using 128MB memory compared to the HD 2600's 256MB! And don't forget that the GeForce 7300GT/128MB was the lower graphics option in the previous model iMac - the 24" could be upgraded to the GeForce 7600GT/256MB graphics which were significantly better! So at first glance it seems that the previous model white iMac with either the GeForce 7300GT or 7600GT graphics is a better gaming machine than the new aluminium iMacs! And I don't expect much improvement with the 2.8GHz Core 2 Extreme in the new 24" as it uses the same graphics as the standard 24".
Mac gamers, now might be the time to think about getting the previous white iMac 24" with the GeForce 7600GT graphics and 2.33GHz CPU, before stocks run out! There should still be some available on special order from Apple or Apple retailers at this date (12 August), but it won't last long. I wish I could afford one because I'd buy it in a flash now I know more about the new models!
14 August Update
There were a couple of reviews posted for the new iMacs yesterday:
Both these reviews have reservations about the new ATI graphics and the glossy screen. Although not comprehensive graphics reviews they both voice disappointment at the lack of improvement to the graphics over the previous GeForce 7300GT/7600GT options. Note that the AppleInsider review shows benchmarks for the old G5 iMac against the new aluminium Intel model, so the gains are NOT over the previous Core 2 Duo iMac and are somewhat misleading!
16 August Update
There is now benchmarking comparing the new top end aluminium iMac 2.8GHz Core 2 Extreme/Radeon HD 2600 Pro 256MB with the old top end white 2.33GHz Core 2 Duo/GeForce 7600 GT 256MB:
Bare Feats Benchmarks
I've been hanging out to see these top end models compared, and I have to say I'm not surprised to see that the old white iMac absolutely FLOGS the new aluminium iMac in most games! In fact the only way to beat the old top end iMac is with a Mac Pro with Radeon X1900 XT graphics!
So serious Mac gamers who want the best Mac game box but can't afford a Mac Pro, should seriously consider trying to get a white iMac 24" 2.33GHz Core 2 Duo with the GeForce 7600 GT 256MB graphics before stocks at Apple run out. If you already have one, then congratulate yourself for not waiting for the 2007 iMac revision, although you would have payed more ;-)
The old white iMac pricing has now been discounted so there is a big saving over its price before the new model was released, making them around the same price as the roughly equivalent aluminium iMac.