The Geekbench score of this MacBook Air is very low, so I have checked clock speeds with HWMonitor / Fake SMC. It runs at a maximum of 800 MHz instead of 1.7 GHz. Another symptom is that the SSD write speed is low and it fluctuates. There is no liquid damage visible. I have checked the four current sensing resistors around U7000, they seem normal. How should I proceed?
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Macbook Air 2011 820-3023-A running at only 800 MHz and SSD write speed is low.
- Thread starter RioRio
- Start date
First of all, welcome to the forum!
Discard SSD, or software issue, running USB macOS.
Or insert a known good SSD from compatible machine.
You can also run corresponding EFI ASD.
Do first PRAM reset 2-3 times.
Discard SSD, or software issue, running USB macOS.
Or insert a known good SSD from compatible machine.
You can also run corresponding EFI ASD.
Do first PRAM reset 2-3 times.
Thank you! 
I have done multiple PRAM Resets. High Sierra from an external HDD has the same issue. Geekbench 5 score: 149 single-core / 387 multi-core.
I have read that I need ASD 3S146 for this MacBook. I will get it from macintoshrepository.org and post the results. The download takes a lot of time.
I have done multiple PRAM Resets. High Sierra from an external HDD has the same issue. Geekbench 5 score: 149 single-core / 387 multi-core.
I have read that I need ASD 3S146 for this MacBook. I will get it from macintoshrepository.org and post the results. The download takes a lot of time.
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Do you note problems in the normal use of the machine?
I have run the EFI ASD and the OS ASD. Both passed.
Yes, the problem in normal use is that the machine is very slow. It is useable but every task feels slow. Installing an OS takes forever.
Any further idea? Is it possible that the CPU itself is partially faulty?
I have another 820-3023-A with RAM problems (3 beeps). I did a RAM reflow, but it failed again after a couple of weeks. Then I've reballed all 16 chips and it failed again after another couple of weeks.
I need to make at least one working board from those two. I could use the Ram from the slow board for the other. Is there a possibility to find out which RAM chip is broken, so I don't have to swap them all? I know that there is also the risk that it's the board itself that is causing the Ram problem...
Yes, the problem in normal use is that the machine is very slow. It is useable but every task feels slow. Installing an OS takes forever.
Any further idea? Is it possible that the CPU itself is partially faulty?
I have another 820-3023-A with RAM problems (3 beeps). I did a RAM reflow, but it failed again after a couple of weeks. Then I've reballed all 16 chips and it failed again after another couple of weeks.
I need to make at least one working board from those two. I could use the Ram from the slow board for the other. Is there a possibility to find out which RAM chip is broken, so I don't have to swap them all? I know that there is also the risk that it's the board itself that is causing the Ram problem...
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You can try swapping the RAM chips, hoping the problem is not CPU in that board.
For the first board, try cleaning ME region in BIOS.
For the first board, try cleaning ME region in BIOS.
A couple of days ago I've already swapped the Bios chip (U6100) from the second board to the first one with no improvement. The scond board had no such symptoms before the Ram failed. After the swap, the first board is still slow. Would it still make sense to clean the ME region? Is it located on the Bios Chip or elsewhere on the board?
"I've already swapped the Bios chip (U6100) from the second board to the first one with no improvement."
Do not expect any improvment, as that chip has dirty ME region for other board!
drive.google.com
Try it as is, don't change serial number; that can be done later, if machine works good.
Do not expect any improvment, as that chip has dirty ME region for other board!
820-3023 clean fix APFS.bin
drive.google.com
@ 2informaticos: I do not own a Medusa and right now it is too expensive for me. I have searched the net for a couple of hours today on how to do it without a Medusa, but I have only found tutorials that don't work for me. Can you recommend me which is the best method to do it when you don't have a Medusa?
@ piernov: thank you. I have already wasted too many hours on this board... I thought that replacing all Ram chips might be the last chance. Replacement boards are still pretty expensive unfortunately.
@ piernov: thank you. I have already wasted too many hours on this board... I thought that replacing all Ram chips might be the last chance. Replacement boards are still pretty expensive unfortunately.
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I've found the youtube tutorial "How to clean ME region on Apple machines" by piernov. I used Linux like in the video. But I only get to the point where I have to open ME Analyzer. It gives me an error message (screenshot in attachment). Then I've tried opening ME Analyzer on a Samsung Laptop with Linux and it gives me the exact same error.
Attachments
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What's the problem???
I already sent you clean ME BIOS...
I already sent you clean ME BIOS...
Reflash the BIOS (U6100) using USB external programmer.
The forum is full with information about BIOS reprogramming...
The forum is full with information about BIOS reprogramming...