It won't just be screen size differentiating the 5.5-inch and 4.7-iPhone 6 handsets according to the latest rumours. Supply chain sources are now stating that the larger-screened iPhone 6 will also feature a more powerful processor than its 4.7-inch stablemate.
Quite how significant the disparity will be isn't clear yet, though Apple analyst Timothy Acuri has stated that it may be simply a matter of the 5.5-inch version shipping with a larger die. This would suggest a more pronounced architectural divide than mere clock speeds, with the suggestion that the larger iPhone may include additional on-die silicon -- perhaps accommodating additional graphics processor cores.
If true, it wouldn't be the first time Apple had popped different processor configurations in devices that would otherwise share identical internals -- last year's iPad Air and Retina iPad Mini tablets (screen size aside) were only separated by processors, with the Air clocked at 1.39GHz and the Mini 1.29GHz. [AppleInsider]