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About BR2032 vs CR2032, if wasn’t needed why Apple uses it?

A BR2032 costs 5x more. BR2032 are appropriate for long duration of slow amperage discharge and have a chemistry adequate for higher temperatures, a must below GPUs. CR2032 are appropriate for fast discharges with relative high amperage in comparison, the chemistry formulation have slow tolerance of high temperatures.

Sorry to hijack a while, but if you don’t mind, what indicator when I must replaced stock BR2032 batteries? Any suggestions?

My machine is Mid 2012 my signature, bought in 2013. Recently I have random freeze after sleeps, clearing NVRAM are interment, is all good but later it would get unknown sleep error again, so I worry about wrong NVRAM value stored incorrectly because of weaken battery .
 
Sorry to hijack a while, but if you don’t mind, what indicator when I must replaced stock BR2032 batteries? Any suggestions?

My machine is Mid 2012 my signature, bought in 2013. Recently I have random freeze after sleeps, clearing NVRAM are interment, is all good but later it would get unknown sleep error again, so I worry about wrong NVRAM value stored incorrectly because of weaken battery .
Don't you read my post at the beginning of the thread? The BR2032 battery only powers the RTC and you have to replace when is below 2,6V.

NVRAM is Non-Volatile RAM, MP5,1 NVRAM is stored inside the same SPI flash memory that stores the BootROM.
 
I am in the same boat with one machine and on other machine is showing strange beaviours, random shutdown, etc....
it looks like an epidemy...
we might have reached the limit of those machine... there is now several post with the same behavior. very interested if any of you guys find a solution.
 
Where’s the EFIDONE LED? Do I need to have powered up to do this? Only the 5V STBY LED lights up when I press the diag button.

Im sure I only did the two firmware upgrades, from 7F to 89, then 89 to 144. I did System Profiler snapshots showing they worked.

i have no experience with hot air rework stations. I’ve only got a basic soldering iron and only have basic soldering skills only.
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And I was using a OEM Radeon HD 5770 1GB with High Sierra. I only installed my RX 580 just to do the 144 upgrade, then put the 5770 back in. Maybe I should try putting the RX 580 in and seeing if it will boot with that.
Thx for the correction about the firmware upgrades. EFIDONE has to be lit when you press the power switch and then DIAG button. Really bricked backplanes, where the SPI flash failed and it's not just corrupted somewhere inside the contents, don't even power on.

Anyway, it's a very real possibility, it's a 7 to 8-year old SPI flash, it's probably already near the third end of the manufacturer intended useful life.

Nowadays, if I have to remove the SPI flash, I replace it with a brand new one. It's so cheap to replace the SPI flash when you have to repair a brick that I don't think twice. The risk of having to do everything again some months down the road it's not worth $2 or $3 that a replacement SPI flash costs.
 
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Where’s the EFIDONE LED? Do I need to have powered up to do this? Only the 5V STBY LED lights up when I press the diag button.

I believe I already told you in a previous message - look at the two banks of LED lights chart above . And yes , you need to be up and running to get some indication on all the LEDs .

Im sure I only did the two firmware upgrades, from 7F to 89, then 89 to 144. I did System Profiler snapshots showing they worked.

It's really unlikely you bricked your logic board by performing a couple / few firmware updates . The main thing is to avoid loss of power during the operations . But if it happened , you might try to install a firmware recovery disc .

i have no experience with hot air rework stations. I’ve only got a basic soldering iron and only have basic soldering skills only.

Few techs even do board level work these days . Maybe 40 years ago , it was different ... I wouldn't worry too much , given the low financial value of the parts involved .

And I was using a OEM Radeon HD 5770 1GB with High Sierra. I only installed my RX 580 just to do the 144 upgrade, then put the 5770 back in. Maybe I should try putting the RX 580 in and seeing if it will boot with that.

A cMP with an EFI 5770 will boot and run Mojave . You just won't have GPU hardware acceleration , so performance will be poor . But it will basically work .
 
It's really unlikely you bricked your logic board by performing a couple / few firmware updates . The main thing is to avoid loss of power during the operations . But if it happened , you might try to install a firmware recovery disc .
Seems you have a very wrong idea on how the SPI flash is constructed and what it's contained inside it. It's not just the firmware, what we call the BootROM, but the NVRAM is there too.

Every time a bit is changed inside the MP5,1 NVRAM, a block of 4096 bytes is erased and re-written. NVRAM changes it's content frequently and dynamically nowadays, it's not in any way like an old PC BIOS or OpenFirmware PRAM time where you set it and forget. Just to you have an idea, the NVRAM volume, and consequently the SPI flash memory, is modified every time when you :
  1. Add, remove or replace a DIMM,
  2. Enable or disable iCloud paramenters,
  3. Add Wi-Fi credentials to iCloud, this don't make sense with a static desktop, but happens every time you add a new network to your MacBook/iPhone/iPad,
  4. Enable TRIM,
  5. Enable SIP,
  6. Change your Mac network name,
  7. Enable, disable or configure Bluetooth,
  8. Change the default sound volume,
  9. Change language/keyboard/other localisation parameters,
  10. Change the default boot disk,
  11. Install macOS,
  12. Boot Recovery,
  13. Boot Windows 8,1/10,
  14. Use NVDIA web drivers,
  15. more.
Every other day I got messages from people about BootROM problems and it's becoming common place bricks caused by cell write retention, where you can't modify the contents of a flash memory cell anymore.

Btw, Firmware Recuperation CD is a excellent idea that never worked in practice. The BootBlock has to be in perfect condition for this even to work. I don't ever repaired a corrupt firmware via Firmware Recuperation CD. Ever.
 
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Nowadays, if I have to remove the SPI flash, I replace it with a brand new one. It's so cheap to replace the SPI flash when you have to repair a brick that I don't think twice. The risk of having to do everything again some months down the road it's not worth $2 or $3 that a replacement SPI flash costs.

@tsialex Where do I find more info about SPI flash and how to do this, where to buy it from? I’ve googled for the last 20mins and all I’m seeing is MacBook references, nothing about cMP.

Is replacing the SPI flash possible with my scenario where I can’t even boot? I don’t have a binwalk or a RomTool dump for this cMP. Is replacing the SPI flash something a novice can do or do you need to be an expert with hot air rework station?
 
@tsialex Where do I find more info about SPI flash and how to do this, where to buy it from? I’ve googled for the last 20mins and all I’m seeing is MacBook references, nothing about cMP.

Is replacing the SPI flash possible with my scenario where I can’t even boot? I don’t have a binwalk or a RomTool dump for this cMP. Is replacing the SPI flash something a novice can do or do you need to be an expert with hot air rework station?
Can't boot situation after firmware upgrades is the most common symptom of a brick.

You can buy an empty SPI flash from Mouser/Digikey/AliExpress/eBay, see below what SPI memory is used with which year-model, program it with the generic MP51.fd using a el cheapo ch341a SPI programmer kit, then replace the suspected SPI flash on the backplane. You can see a step-by-step process that I documented back in September 2018, see my screenshots.

Year model:SST 25VF032BMXIC MX25L3205DMXIC MX25L3206E
early-2009usuallyrarelycan be used as replacement for all years
mid-2010rarelyusuallycan be used as replacement for all years
mid-2012can be used as replacement for all yearsrarelyusually

Since the SPI flash memory (U8700) is a SOIC 200-mil, it's very difficult to remove it with a common soldering iron, you will need a chip-quick low melt solder or something similar to desolder it when using a common soldering iron.

It's a lot easier to install it then to remove. I prefer to use a hot air rework station to remove, less chance of lifting a pad or a trace, but surely can be done without hot air tools.
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Btw, MP51.fd will resurrect your backplane, but this firmware image don't have any hardwareIDs and your Mac Pro won't connect to iCloud, FaceTime or Messages. Most times you can extract the needed NVRAM stores (3rd and 4th) and the MLB sector from the original SPI flash. Even if the original SPI is totally dead, with some work and calculations, I can reconstruct the hardwareIDs and make a fully working BootROM using the data from the ESN label on the back of the case and the MLB label near of the AirPort Extreme connector.

Btw, BBS won't work to personalise a backplane flashed with just MP51.fd. BBS requires that the backplane have a working MLB/LBSN sector and that the 3rd/4th stores exist inside the NVRAM volume, MP51.fd image have a totally empty NVRAM and MLB/LBSN sectors (as in totally full of zeros).
 
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Having read your posts, I know I'm completely out of my league with even considering replacing the SPI flash, let alone programming and other steps involved. My brain kinda exploded reading what you've been doing - you've got some great skills there. I do truly appreciate your sharing all this information. I'm in discussions with the company that sold me the cMP as to the next steps. Nga mini nui
 
Having read your posts, I know I'm completely out of my league with even considering replacing the SPI flash, let alone programming and other steps involved. My brain kinda exploded reading what you've been doing - you've got some great skills there. I do truly appreciate your sharing all this information. I'm in discussions with the company that sold me the cMP as to the next steps. Nga mini nui
I know that for most people this is too complex to do, maybe even more costly than to get a replacement backplane in the US, but for people outside US/Canada, where the cost of a replacement backplane is considerable, it's a tried and true solution to repair a brick.

A ch341a SPI flash programmer kit can be bought for less than $15 from Amazon/AliExpress/eBay/etc, a Chip-Quick and a replacement SPI are inexpensive too.

If you already have the tools and skills, you can repair a MP5,1 brick with around $30 of supplies, maybe even less, in an afternoon.
 
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Don't you read my post at the beginning of the thread? The BR2032 battery only powers the RTC and you have to replace when is below 2,6V.

NVRAM is Non-Volatile RAM, MP5,1 NVRAM is stored inside the same SPI flash memory that stores the BootROM.

Thanks for detailed answer, it looks I am wrong about NVRAM contents are BR2032 dependent, since it was stored in SP1 flash chips.

I don’t sure any method to checks battery voltage on my machine unless I took them out and go with multimeter (just got random sleep again today), but I will go with new BR2032 anyway, just ordered 4 pieces of them.

Cheers!!
 
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It has been reported that a mac pro with a totally dead Clock Battery is booting immediately after plugging the mains cable in.
 
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@tsialex is the Matt card a viable option for people that don’t have the skills to replace the SPI flash chip?
 
@tsialex is the Matt card a viable option for people that don’t have the skills to replace the SPI flash chip?
Yes, with two serious problems.

The BootROM image cmizapper sends you is a clone from a mid-2010 Mac Pro that still have MP51.007F.B00, from August 2010. All Mac Pro matt cards have the exactly same dump, this was checked with several matt card owners like @startergo, @Plutonius, @campodoro74 and myself. With this EFI firmware version you can only boot HFS+ macOS installs (10.6 to 10.12, 10.13 installed with HFS+). This is the first problem.

The second problem rely on the fact that all matt cards are clones and when Apple detects it, iCloud/iMessage/FaceTime are blocked. To make a MATT card work correctly you boot a macOS HFS+ install and flash it with the correct BootROM dump of your Mac Pro. Once you have the correct image for your own Mac Pro flashed, it's a top notch product.

The real show-stopper problem happens when you don't have the BootROM dump. Now you have a Mac Pro clone, that only boots HFS+ and that can't connect to iCloud/iMessage/FaceTime and you have to correct this by himself.
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This is the hardware overview from @campodoro74 matt card that he sent me, only the CPU Tray serial number are the real one, all other hardwareIDs in the SPI flash are clones:
714981-0eed588911cb504b6e8b456d80f8a9fe.jpg
 
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Yes, with two serious problems.

The BootROM image cmizapper sends you is a clone from a mid-2010 Mac Pro that still have MP51.007F.B00, from August 2010. All Mac Pro matt cards have the exactly same dump, this was checked with several matt card owners like @startergo, @Plutonius, @campodoro74 and myself. With this EFI firmware version you can only boot HFS+ macOS installs (10.6 to 10.12, 10.13 installed with HFS+). This is the first problem.

The second problem rely on the fact that all matt cards are clones and when Apple detects it, iCloud/iMessage/FaceTime are blocked. To make a MATT card work correctly you boot a macOS HFS+ install and flash it with the correct BootROM dump of your Mac Pro. Once you have the correct image for your own Mac Pro flashed, it's a top notch product.

The real show-stopper problem happens when you don't have the BootROM dump. Now you have a Mac Pro clone, that only boots HFS+ and that can't connect to iCloud/iMessage/FaceTime and you have to correct this by himself.

Good to know, especially the part about the every bit of data written = 4096 byte erase/re-write - thank you. I'm going to order one and have the cmizapper team flash the reconstructed 144 version of my bootrom to the chip before shipping it.
 
Good to know, especially the part about the every bit of data written = 4096 byte erase/re-write - thank you. I'm going to order one and have the cmizapper team flash the reconstructed 144 version of my bootrom to the chip before shipping it.
Flash your self using flashrom/ROMTool, imagine the nightmare scenario where they use your dump for the next batch of Mac Pro MATT cards made…

The SPI flash sectorization and the fact that NVRAM is inside the SPI flash are often overlooked when you think of the 100.000 expected re-writes of the SPI flash. SPI flash failure is common nowadays.
 
Flash your self using flashrom/ROMTool, imagine the nightmare scenario where they use your dump for the next batch of Mac Pro MATT cards made…

The SPI flash sectorization and the fact that NVRAM is inside the SPI flash are often overlooked when you think of the 100.000 expected re-writes of the SPI flash. SPI flash failure is common nowadays.

Sound advice - thanks again.
 
With this EFI firmware version you can only boot HFS+ macOS installs (10.6 to 10.12, 10.13 installed with HFS+).

so I flashed my matt card to 144.0.0.0

next i will it flash with a clean MP5.1.fd (?)
use it only for fast testing a board
 
so I flashed my matt card to 144.0.0.0

Alex is recommending to do the flashing ourselves and not to share our bootrom with third-parties. No problem in flashing any bootrom version to the Matt card. It just requires extra effort on my part as I'll have to switch my GPU back to the GTX 780 to load up High Sierra on HFS+ then flash my v144 rom using ROM Tool
 
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my mattcard has the same serial as in the picture alex posted
but with bootROM version 144

i use it only for testing a bricked board
and if the SPI chip is fully dead, I will exchange it
 
my mattcard has the same serial as in the picture alex posted
but with bootROM version 144

i use it only for testing a briked board
So, one more to the list of clones. You just upgraded to 144.0.0.0.0 without changing to your Mac Pro real dump.
 
So, one more to the list of clones. You just upgraded to 144.0.0.0.0 without changing to your Mac Pro real dump.

yes, only i flash it with 144 over the data of the matt card
comes also with MP51.007F.B00


but i wrote i will flash it with MP51.fd
 
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yes, only i flash it with 144 over the data of the matt card
comes also with MP51.007F.B00


but i wrote i will flash it with MP51.fd
No problem with that, you are using it as a diagnostic tool. Just don't use it to connect to your iCloud/Messages/FaceTime or you will have to call Apple down the road.
 
yes of course i only use my matt card for diagnostics
with an macOS only SSD and without network connection
 
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