Asus confirmed that his ZenFone 3 in most powerfull version (Deluxe) will be equipped with Snapdragon 821. And here you have full specyfication of ZenFones:
System: Android 6.0;
Screen: 5.7" FHD, 2.5D, Gorilla Glass;
CPU: Snpdragon 820/820/821;
RAM: 4/6/6GB;
Storage: 32/128/256GB + microSD;
Cameras: /16/16/23MP rear and 8MP front;
Battery: 3000mAh with fast charging;
Other: dual SIM dual standby, hybrid slot for nano SIM/microSD, fingerprint scanner, USB Type-C;
Size: 152.59x77.38x7.69mm;
Weight: 155g;
Price: TWD 15990 ($479)/TWD 17990 ($559)/TWD 24990 ($776).
Different versions are seperated with slashes.
As we can see Deluxe version is priced much higher then normal versions but processor, camera and storage is also much better/faster.
Source: gsmarena via Asus