The 21.5” uses a soldered mobile CPU, so no - it can’t be done without a donor CPU (or a rare NOS BGA CPU that was never used), a rework machine and a lot of experience - and possibly a schematic to fill in the VRM blanks the i7 uses, but not the i5. That, or a new motherboard and the blank board serializer tool.
That’s not a problem on the LGA 27” because Apple builds one board and multiple configurations, but the mobile CPU base board can be cost reduced safely with different parts based on the manufacturing code since the CPU is board specific and not designed to be interchanged - the board gets replaced when the CPU dies whereas on a 27” anyone with the guts and an OOW machine can replace the CPU individually. Refer to the guide and you’ll see how difficult it is to do.
Even if you can, the job is such a burden unless you plan on replacing the board with a significantly faster board, the risk (and expensive repairs if you screw up) is pointless if all you get is 10% more performance because you didn’t spend an extra $50 to max out the CPU. Only do this if:
- You’re a good DIYer
- You are willing to max it out CPU wise and go all out (and can afford to!)
- Will see major performance improvements.
If you will not get all 3 benefits and aren’t willing to get a top end board, don’t.
5条评论
hi Nick thank you for the prompt response.
I guess I should have rephrase my question! To upgrading the logic board rather than upgrading the CPU.
So the bottom line you’re saying that I cannot swap the core I5 logic board with a core i7 logic board. Correct?
由 Chekad Sarami 完成的
@chikitin You can swap it, but it may be cost prohibitive. It's also downright risky unless you go all out for the top end i7 like I mentioned with AIOs.
i5 to i7? I don't think it's worth the risk unless you have a very low end i5 and can gain ~10,000+ CPU performance points with the top end i7 from your old board.
由 Nick 完成的
Just to be clear, was your answer about replacing the CPU and not the Logic board? Right? The price difference of the two mother boards is just 20 dollars. I just need to know if i can simply buy the EMC 2742 logic board and swap it with the old one. Thank you again, Nick for the prompt response.
由 Chekad Sarami 完成的
@chikitin It wasn't specific to CPU or board swaps - it could go either way.
由 Nick 完成的
Thank you! I asked you because, a seller of the EMC 2742 logic board had listed the logic board compatible with my logic board EMC 2638 which as Core i5 CPU!
由 Chekad Sarami 完成的