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K4100m black screen help pls

Bboykes

Bboykes

macrumors newbie
Original poster
Nov 12, 2021
23
5
Hi I got 2009 27 in i5 imac I bought k4100m. I took eeproom ic out m25 . I flashed new rom with my eeproom universal programmer not clip this is expensive reader which I use for fixing lcd tvs... I wrote rom which I download here . I plugged in to imac its just black screen .i can hear boot sound and when I press keyboard keys it makes sound but no backlight or display. I checked motherboard light I can see 3 lights on there any ideas pls help me its my daughter birthday present
 
On the first post of the GPU thread there is a section about known issues, you should not have missed it:

Black Screen:
After complete installation of the iMac the internal LCD can stay black, only three status LED light up. This is the black screen software issue. Normally you can get around it (temporarily) by pressing alt/option on boot. Late 2009 system you will face (only there) a more severe variant. After a PRAM reset the LCD gets and remains black. To fix this for all iMacs a kernel extension needs to be patched at best in advance. Only after booting into this patched macOS the internal LCD will come back. Use this package installer to solve this issue with all NVIDIA cards on all systems up to macOS Catalina. Do not use this package on Big Sur and later. Alternatively OpenCore (e.g. OCLP) with agdpmod=vit9696 in the boot-args fires up the LCD after a PRAM reset or GPU change, too.

The only way to get this done now is using an external display.

Please do not use personal messages to ask questions and just use the appropriate existing thread instead of creating a new one nobody is able to find....

Edit: Best solution if you plan to install Big Sur is just using OCLP.
 
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Thank you so much i ordered mini display cable so I can connect to tv. As soon as cable come im gonna install big sur ocpl thank you
 
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Ausdauersportler said:
On the first post of the GPU thread there is a section about known issues, you should not have missed it:

Black Screen:
After complete installation of the iMac the internal LCD can stay black, only three status LED light up. This is the black screen software issue. Normally you can get around it (temporarily) by pressing alt/option on boot. Late 2009 system you will face (only there) a more severe variant. After a PRAM reset the LCD gets and remains black. To fix this for all iMacs a kernel extension needs to be patched at best in advance. Only after booting into this patched macOS the internal LCD will come back. Use this package installer to solve this issue with all NVIDIA cards on all systems up to macOS Catalina. Do not use this package on Big Sur and later. Alternatively OpenCore (e.g. OCLP) with agdpmod=vit9696 in the boot-args fires up the LCD after a PRAM reset or GPU change, too.

The only way to get this done now is using an external display.

Please do not use personal messages to ask questions and just use the appropriate existing thread instead of creating a new one nobody is able to find....

Edit: Best solution if you plan to install Big Sur is just using OCLP.
Click to expand...
Thank you very much i install patch all working now quick question if u dont mind when I go mac fan control there no gpu tempture showing any ideas
 
Ausdauersportler said:
Check again the first post of the GPU thread there is a FAQ!
Click to expand...
Hi just let u know if u want to add ur tutorial I use rt809h universal programmer to flash rom and it worked perfect. reason I say this coz I read on here people use universal clip and they couldn't read if people buy this programmer it read most of mx25 eproom . Little advise to people who don't want to messing all you need desolder eeprom put on programmer it does auto scan for ic id click erase than Flash it take 5 minutes
 
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Ausdauersportler said:
On the first post of the GPU thread there is a section about known issues, you should not have missed it:

Black Screen:
After complete installation of the iMac the internal LCD can stay black, only three status LED light up. This is the black screen software issue. Normally you can get around it (temporarily) by pressing alt/option on boot. Late 2009 system you will face (only there) a more severe variant. After a PRAM reset the LCD gets and remains black. To fix this for all iMacs a kernel extension needs to be patched at best in advance. Only after booting into this patched macOS the internal LCD will come back. Use this package installer to solve this issue with all NVIDIA cards on all systems up to macOS Catalina. Do not use this package on Big Sur and later. Alternatively OpenCore (e.g. OCLP) with agdpmod=vit9696 in the boot-args fires up the LCD after a PRAM reset or GPU change, too.

The only way to get this done now is using an external display.

Please do not use personal messages to ask questions and just use the appropriate existing thread instead of creating a new one nobody is able to find....

Edit: Best solution if you plan to install Big Sur is just using OCLP.
Click to expand...
 
Hi mate sorry to been pain can I ask is this normal when I go to about this mac I can see rom showing on there but when I move any page with mouse it does this I upload pictures
 

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Using dosdude1 on iMac 2009 install the legacy video patch which will break all video acceleration in your metal K4100,
you can either disable it or you can use OCLP to install Mojave and later, which is the best solution you can have on your system.

Please give the this post a try and read the

Spoiler: Update your (mac)OS on the metal capable iMac

Al your questions have been asked and answered a hundred times before just because you guys do not want to read the docs. I cannot really carry all of you thru this again and again. Please help me!
 
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Unfortunately I cannot answer to your PM. Check my complete signature…

You have not been the first falling into this pit. The ultimate way to use your metal modded iMac 2009 system in using OCLP, not the dosdude1 patcher.
 
Below of each of my posts there is a so called signature (like below eMails).
Mine contains two systems I am using, the link to the iMac 2011 GPU thread and another line.

You should see this! If not use Safari on the iMac to the read this forum….not a mobile device.
You can add your own signature to your account here, too.
 
Im so so angry It stuck on 12 minute remaining than gone back 13 than 12 than this appear and shut down
 

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This happened during installation? Reboot, possibly it continues where it stopped. Give it time, leave the iMac. It runs unattended.
Otherwise restart installation.
It is 1am here.
 
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Yeah its done during installing on 12 minutes remaining it does i tried all night it always does it i even wipe harddrive fully still does it now i don't even have recovery im stuck i cant go back coz I wiped fully drive i can't install big sur coz it fails i don't know what to do
 
You need another mac to create another USB installer. The latest OCLP has this feature included, i.e. you can use it to download a macOS version and create an USB installer.

The only explanation I have is: Your USB pen drive is broken and you have a damaged installer. There is no known issue with Big Sur installation.
 
Yeah its done during installing on 12 minutes remaining it does i tried all night it always does it i even wipe harddrive fully still does it now i don't even have recovery im stuck i cant go back coz I wiped fully drive i can't install big sur coz it fails i don't know what
Ausdauersportler said:
You need another mac to create another USB installer. The latest OCLP has this feature included, i.e. you can use it to download a macOS version and create an USB installer.

The only explanation I have is: Your USB pen drive is broken and you have a damaged installer. There is no known issue with Big Sur installation.
Click to expand...
Hi mate I made a few usb opencore again but it doesn't show boot menu it comes up this any ideas
 

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Bboykes said:
Yeah its done during installing on 12 minutes remaining it does i tried all night it always does it i even wipe harddrive fully still does it now i don't even have recovery im stuck i cant go back coz I wiped fully drive i can't install big sur coz it fails i don't know what

Hi mate I made a few usb opencore again but it doesn't show boot menu it comes up this any ideas
Click to expand...
You simply did not boot OC! Press alt/option on boot and select the boot EFI entry, then boot the installer and go ahead.
 
Ausdauersportler said:
You simply did not boot OC! Press alt/option on boot and select the boot EFI entry, then boot the installer and go ahead.
Click to expand...
Im pressing alt option but doesn't show any option and than that msg comes and goes off do u think gpu failed
 
No, you simply do not have OpenCore installed properly onto the USB or internal SSD. You need to boot a working macOS on this system to install it back onto the internal SSD.

Try to install High Sierra on a separate partition and use this as fall back. Install OC, boot the Monterey installer and install it into another separate partition. Do not share the same APFS! Use the installer disk utility to create this new APFS!!

Q: Do you have by any chance an external USB HDD/SDD which can be used to install a High Sierra version?
 
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Ausdauersportler said:
BTW: You can always start the internet recovery:

www.ifixit.com

How to Start Up a Mac in Internet Recovery Mode

If your Mac isn't connected to a storage drive with macOS installed, or your boot drive is corrupted, the computer will flash a question mark...
www.ifixit.com www.ifixit.com
Click to expand...
I manage install high Sierra now I'm building opencore again wuick question there is 2 option on there when u build opencore one security option sip boot and some boot is it false or true and shall I set metal gpu status to nvidia i upload picture im sorry to bother u again
 

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