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What’s inside new rMBP ?

Found a screenshot of new rMBP with amd card inside:

Device-id is 6821, looking at it’s closest brother 6820 – https://pci-ids.ucw.cz/read/PC/1002/6820

It’s mobile variant of cape verde chip that’s found in radeon hd 7770.
640 shaders, 16 ROPs, 40 TMUs, 128-bit bus.

And, just x8 pcie ?

Well, x8 pcie 3.0 would be equal to x16 pcie 2.0, but why?

The cpu has total of 16 pcie 3.0 lanes, x8 to gpu, two of x4 to TB controllers?

gtx 750ti is much faster than hd7770, cosuming less power, if only apple would include gm107 into new rmbps…

Comments

  1. Yolanda
    May 23rd, 2015 | 3:31 pm

    х8 of very fast PCI-E 3.0 bus is too enough for not a fast GPU. It’s enough even for fastest desktop boards, then they work on Haswell boards in SLI, where is only x8 lines availably for each GPU.

  2. aberracus
    May 28th, 2015 | 5:57 pm

    OpenCL ? Nvidia OpenCl support is not so good.

    FCPX will fly on these card not as fast on the gtx 750

  3. Spacedust
    May 29th, 2015 | 6:11 pm

    Now let’s make HD7770 EFI rom !

  4. smalm
    June 8th, 2015 | 9:32 pm

    x4 PCIe 3.0 is required for the PCIe SSD (OEM variant of Samsung SM951).
    As the CPU only provides 16 lanes (and x12 doesn’t work) Apple had no choice but to only use x8 for the GPU.
    But this way the SSD can reach over 2GB/s (read).

  5. Mike
    June 23rd, 2015 | 2:57 pm

    @Spacedust

    Yes please ! I’d play for a hd7770 efi rom !

  6. Mike
    June 23rd, 2015 | 2:59 pm

    pay

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