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iMac 2011 GPU Upgrade Display Problem GTX675MX
- Thread starter moorhad
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When I start the iMac it powers on.
But I get no screen on the iMac.
When I connect my Thunderbolt Display
Into the iMac I get a screen but only on the
Thunderbolt Display.
The screen of the iMac is black.
It also doesn't recognize the iMac screen
in the settings.
But I get no screen on the iMac.
When I connect my Thunderbolt Display
Into the iMac I get a screen but only on the
Thunderbolt Display.
The screen of the iMac is black.
It also doesn't recognize the iMac screen
in the settings.
Now I get it. How I know, you need modified bios or drivers for videocard. Also, can you make screenshot for proofing?
You should probably hide your serial number - it's visible in those photos.
It also sounds like the 675MX needs a custom firmware to make it compatible with the iMac.
I assume all the internal cables have been reconnected? The iMac's internal display is run over a DisplayPort connection - this may not be visible to the new GPU if it's a port on the logic board without a specific Mac firmware.
It also sounds like the 675MX needs a custom firmware to make it compatible with the iMac.
I assume all the internal cables have been reconnected? The iMac's internal display is run over a DisplayPort connection - this may not be visible to the new GPU if it's a port on the logic board without a specific Mac firmware.
People have asked users that have the 675/680 GPUs to use the firmware dump tool to extract it so that it can be used to flash other cards, but as far as I know this has been unsuccessful with the late 2012 iMac for some reason.
Macvidcards might have more information.
I believe the 2011 iMacs used a standard LVDS connection and the 2012 and later switched to an internal MiniDisplayPort connection. They may be physically identical connectors but they used different protocols. Either that, or you missed a connection or damaged one. The two suspects would be the main data cable or the backlight cable, though if it were the latter the machine would behave as if the internal display was attached.
What if you could get the bios from the GTX 680MX of a 2012 iMac and flash it onto the GTX 675MX? That might work
The issue is not typical of a firmware issue...
Typically if a PC video card is installed in a Mac then you will not get boot screens on any display but once the OS loads and the OS drivers are running then you get full display.
This is a different kind of incompatability.
Also, you should not flash a 675 with 680 firmware. Stick with like for like if you're going to play around with something like that.
Typically if a PC video card is installed in a Mac then you will not get boot screens on any display but once the OS loads and the OS drivers are running then you get full display.
This is a different kind of incompatability.
Also, you should not flash a 675 with 680 firmware. Stick with like for like if you're going to play around with something like that.