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iFixit tears down iPhone 4S, 512MB RAM confirmed, new Qualcomm MDM6610 chip discovered

The teardown is in progress. Notes of interest:

  • The extra .05W/hrs battery increases talk time by an hour but for some reason (likely additional background processes with notifications), standby time is reduced from 300 to 200 hrs
  • Pentalobe Screws, again?”
  • The A5 processor is rated at 1GHz (like iPad obv.) but is underclocked for battery saving purposes. That doesn’t mean an update (or hack) in the future could boost speed to iPad levels.
  • The iPhone 4S logic board bears a close resemblance to its stateside CDMA counterpart.
  • The Qualcomm chip updated from MDM6600 to MDM6610. There isn’t much out on the 6610 right now but we’re investigating.
  • It looks like there really is only 512MB of RAM. AnandTech says:

The second confirmation iFixit’s teardown gives us is the size of the A5’s on-package memory: 512MB. A quick look at the image above yields the Samsung part number: K3PE4E400B-XGC1. Each highlighted E4 refers to a separate 2Gb LPDDR2 die. The A5 features a dual-channel LPDDR2 memory interface, thus requiring two 32-bit die to fully populate both channels. The final two characters in the part number (C1) refer to the DRAM’s clock period, in this case 2.5ns which indicates a 400MHz clock frequency (F=1/T). My assumption here is Samsung’s part number is actually referring to clock frequency and not data rate, implying there are a pair of LPDDR2-800 die in the PoP stack. It’s not entirely uncommon to run memory at speeds lower than they are rated for, a practice we’ve seen in graphics memory in particular for as long as I can remember, so I wouldn’t take this as proof that Apple is running at full LPDDR2-800 speeds.

We’re updating as things develop.