EFI 1.8 “This software is not supported by your system” on iMac 21.5 2010

Hello,

I’ve been trying to install/upgrade the EFI of an iMac 21.5 inch 2010 model due to the fact that it’s boot time is really bad despite having an i5 660, 16 gb of ram and an SSD installed. When downloading this from the 21.5 2010 iMac page, opening the file up gives me the error listed above. I’ve gone as far as downgrading to MacOS X Lion to try and fix this, being on 10.7.5 and it says 10.7.3. Do I really have to somehow go back 2 versions? I don’t even have a proper Boot ROM version, it just being 99.0.0

thanks for any help

Earlier Mac models

Posted on Jul 18, 2024 2:00 AM

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HWTech

Level 9

69,464 points

Posted on Jul 23, 2024 1:45 PM

Apple updates the system firmware both SMC & BootROM through macOS updates. If you have installed macOS 10.13.6, then the iMac should be on the latest firmware. You can use the links provided by @BDAqua & @MrHoffman to confirm if your iMac is running the latest firmware.

Those old firmware updater links are very old and won't give you the latest firmware for the system. Plus when the requirements mention macOS 10.6.7, then it literally means only 10.6.7, not 10.6.7 or later....those firmware updates are OS specific. So if a firmware update was provided for only macOS 10.6.7, then that firmware revision would be extremely old. In fact macOS 10.12.4 updated the firmware to allow for access to Internet Recovery Mode, the online Apple Diagnostics, and knowledge of the APFS file system for booting.

I don't know what tool you are using in those screenshots, but if it is the Apple firmware updater, then it probably does not recognize the major changes made to the firmware by later versions of macOS. Post a screenshot of the Apple System Profiler showing the hardware information and the firmware revisions both for the SMC & BootROM....just make sure to edit out the system serial number from the screenshot.

If your system is slow, then the expanded 16GB of RAM would be one possibility since Macs are very picky about the memory they use.

Which Crucial SSD are you using in this iMac? If it is the BX500 series, then that can easily be the problem since the BX500 SSD is pure junk since it can perform worse than a hard drive. The Crucial MX500 series is good and should work fine. Or use the OWC Mercury Electra 3G SSD which utilizes only a SATA II controller so there should be no issues auto negotiating the SATA Link speed which can happen with some SATA III SSDs. This is why OWC is still providing SATA II based SSDs (hence the 3G designation for 3Gb/s the SATA II max speed).

Have you tried running the Apple Diagnostics to see if any hardware issues are detected?

If you have an SSD other than the BX500 series, then you can check the health of the SSD by running DriveDx (free trial period) and posting the complete text report here using the "Additional Text" icon which looks like a piece of paper on the forum editing toolbar so I can review it.

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30 replies

Jul 25, 2024 1:23 AM in response to HWTech

here ya go,

I am using a MX500 drive that I ripped out of a windows computer and formatted it, so on every other computer I’ve gotten good read/write speeds except this computer. I’ll try maxing out the ram although it may not make that much difference. I attempted to use the Apple hardware diagnostics to find the problem by a bootable usb program as the original one no longer existed due to not having the original disk. Although when it was going through the “Probing your hardware, this may take a minute”, everything froze, not even the mouse was moving.

Even when I booted into it, it was lagging heavily, having to wait around 3 seconds for the screen to refresh and show my mouse in its new spot if I moved it.This happens when I try to run things off a bootable usb etc open core legacy, EFI boots for other items such as the MacBRTool, and more

Old Toad

Level 10

215,864 points

Jul 25, 2024 9:25 AM in response to Justacrappyrepairer

Save your money. Maxing out the RAM will have nothing to do with read and write or boot (if you're booting from the drive) speeds. It's the connection speed of the drive that is important and that is influenced greatly by the enclosure and chip that the drive is in as well as the type of connection.

Jul 25, 2024 4:04 PM in response to HWTech

Ill try using the online diagnostics tool. I don't actually have any sort of patchers installed, just anytime I try to boot into any kind of EFI bootdisk, it lags quite a bit, to the point whenever I move the mouse, i have to wait three seconds before I can see its new position on the screen

Jul 18, 2024 4:42 AM in response to Justacrappyrepairer

If you have previously updated the EFI to a later version than 1.8, perhaps the installers are set up to prevent you from downgrading.

Jul 18, 2024 6:01 AM in response to Servant of Cats

Okay, so hypothetically it would be better just switching back to a hard drive. Thanks for the help :)

Jul 21, 2024 2:42 PM in response to den.thed

apologies for the last reply, I used a crucial 500gb SSD which I know are notorious for failing, but I’ve tried other SSDs and the slow boot speed still persist

Jul 21, 2024 3:41 PM in response to Old Toad

Nope, I know those don't do much stuff so I haven't bothered either

Jul 22, 2024 6:32 AM in response to MrHoffman

I ended up trying to use the MacBRTool, and got an error, doesn’t look good.

MrHoffman

Level 10

146,761 points

Jul 22, 2024 8:04 AM in response to Justacrappyrepairer

Yeah, that doesn’t look promising. The firmware here looks very sick. Or the hardware.

BDAqua

Level 10

250,259 points

Jul 25, 2024 7:19 AM in response to Mal-S

👍

Jul 27, 2024 7:08 AM in response to BDAqua

Yep, here you go. The major and minor issues i know about and aren't causing harm, just wondering if there is a deeper issue going on here.

Report

Jul 27, 2024 7:10 AM in response to BDAqua

Ive installed all security updates straight from the first one in safe mode, although that doesn't seem to help at all :(

Jul 27, 2024 7:13 AM in response to HWTech

SSD report

Also I'm getting 100% from pretty much everything for the ssd

BDAqua

Level 10

250,259 points

Jul 27, 2024 8:29 AM in response to Justacrappyrepairer

One problem...

TRIM: No

And who knows with OCLP

BDAqua

Level 10

250,259 points

Jul 27, 2024 7:05 PM in response to HWTech

👍

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EFI 1.8 “This software is not supported by your system” on iMac 21.5 2010