Apple iPhone 3GS - boosted brain

Hirdetés

Hardware changes

There is only a minimal amount of change on the outside, the new iPhone looks just like its predecessor, it only gained some weight, so it now weighs 135 grams. It has a size of 115.5 x 62.1 x 12.3 mm, it’s also available in black and white, but we can notice on the back that the storage capacity has doubled, it increased from 8/16 GB to 16/32 GB. Although it’s not written on the phone, the RAM has also doubled, we now have 256 MB.

The case is of the same quality, everything is made of shiny plastic (with the exception of the stripe around the front), which is a great fingerprint-magnet, but at least it looks good. The fittings don’t seem perfect, hair or moisture could get stuck in the small hole, which might be a bit annoying, I think this should have been avoided. The display still has a diagonal of 3.5”, a resolution of 320 x 480 pixels, which doesn’t sound too much, but the thing is that besides Samsung’s AMOLED screens, nothing looks as good as iPhone’s.

[+]

The main changes have affected the inside: besides doubling storage space and memory, the new iPhone has a new processor and video chip, instead of the 412 MHz ARM11 CPU, it now has a 600 MHz chip, based on a Cortex A8 core, while the PowerVR MBX-Lite graphical chip has been swapped out to a PowerVR SGX – this is the same processor that Palm Pré uses. Although you can’t guess it from its name, introducing the Cortex A8 means a generation leap at ARM architecture chips, as ARM11 represents the sixth generation and A8 is from the seventh gen. This of course means that besides the better clock speed, the Cortex A8 also has better features: while iPhone 2G/3G’s CPU had a simple basic vector floating point unite, Cortex has a more advanced SIMD unit with its own pipeline, advertised under the brand name NEON – this pipeline has 10 stages, while the main integer pipeline has 13. SIMD stands for single instruction multiple data, processing units based on this technology can apply an instruction to multiple units of data at the same time, which comes in handy at graphical tasks and multimedia. Cortex A8 has two times as much double-precision floating point number registers, while L1 cache size increased from 2 x 16 kB to 2 x 32 kB and it also has 256 kB of L2 cache. Otherwise A8 is a superscalar core, it has two ALU’s that can execute two independent instructions, but it doesn’t support out-of-order instructions. This means that it can read, decode and execute two RISC instructions (it supports multitasking), but it can process these instructions in order. On the whole we can say that Cortex A8 is the most advanced CPU we can find in mobile phones nowadays.

The graphical core is also from a new generation, SGX is from the fifth, while MBX Lite was from the fourth PowerVR generation – I’d like to note that the first was used in Kyro PC graphical cards, while the second has been featured in the Sega Dreamcast game console. There are more types of SGX, the most basic is SGX520 and the most powerful is SGX540. There were rumors before the launch of the new iPhone that the handset will feature the 520 edition, which is although the weakest from the series (it has a single 200 MHz USSE pipe), it can render 7 million polygons and 250 million pixels per second, which is seven times as much in geometrical speed and it has a three and a half times faster fill rate than the MBX Lite in iPhone 3G. The truth is even better, as according to officially unconfirmed information, iPHone 3GS has the SGX535 chip, which can pump out 28 million polygons per second – Palm Pré has SGX530 that has a speed of 14 million polygons/second. If we also consider OpenGL ES 2.0 support we can say that the new hardware turned the new iPhone into a real gaming platform, although it wasn’t bad already.

PowerVR graphical chip generations

A cikk még nem ért véget, kérlek, lapozz!