iM 4,1-14,4 2011 iMac Graphics Card Upgrade

[greenbirdlx]

My experience was a resounding success, installing a 780M in my 2011 21.5" i7. I did have to modify the hard drive case a bit, there was an interference with the new card since it is "taller" than the stock card.

I had to omit one of the PCB screws, and sand out a small bit of one of the plastic air dams. If I were to do it again, I'd remove the entire PCB before grinding on the hard drive case and reinstall it after. I used an old shirt to make a pseudo-surgical cover, and vacuumed up any other grinding I could find after.

Booted up in OS X and was good to go, no issues! Installed CUDA drivers just in case. Switched to Bootcamp Windows 10, had a 480p resolution to start, but was able to install drivers and now runs great. Attached are some pics, hopefully they help anyone else.

My source was ebay, bought on June 13, 2016 for $295 shipped.
DELL Alienware M18x M17x Nvidia Geforce GTX 780M 4GB Video Card N14E-GTX-A2 Used
Lot AWDA-GTX780

P.S. I had been lurking this thread for awhile, registered just to document and say thanks to those that tried it and reported back first!

 

[bjoroy]

Great thread. Been lurking for a while. Just ordered a 780M (pulled from Dell/Alienware) + more RAM + SSD for my mid-2011 27". Will post back with results

 

[nin808]

EDIT: I originally posted with some problems but I got them all figured out. So consider this a success report: mid-2011 27" iMac; El Capitan/Windows 10; 32 GB of RAM; 480gb SSD added (240 for OS X, 240 for Windows); NVIDIA 780m (Alienware) GPU upgrade. Everything is running great!

Of course, no boot screen or brightness controls, but I never really used brightness and the no boot screen is just a minor inconvenience now that the OS itself loads so fast.

Thanks to everyone participating in this thread.

 

[frets]

My experience was a resounding success, installing a 780M in my 2011 21.5" i7. I did have to modify the hard drive case a bit, there was an interference with the new card since it is "taller" than the stock card.

I had to omit one of the PCB screws, and sand out a small bit of one of the plastic air dams. If I were to do it again, I'd remove the entire PCB before grinding on the hard drive case and reinstall it after. I used an old shirt to make a pseudo-surgical cover, and vacuumed up any other grinding I could find after.

Booted up in OS X and was good to go, no issues! Installed CUDA drivers just in case. Switched to Bootcamp Windows 10, had a 480p resolution to start, but was able to install drivers and now runs great. Attached are some pics, hopefully they help anyone else.

My source was ebay, bought on June 13, 2016 for $295 shipped.
DELL Alienware M18x M17x Nvidia Geforce GTX 780M 4GB Video Card N14E-GTX-A2 Used
Lot AWDA-GTX780

P.S. I had been lurking this thread for awhile, registered just to document and say thanks to those that tried it and reported back first!

I have been trying to install the Nvidia Web Driver from their website but I get an error message saying its not compatible on my El Capitan. Is there another place I can get drivers for the GTX780m Nvidia Web Driver? Do we really need the nvidia web driver in any case?

Cheers

 

[madeirabhoy]

Great thread. Been lurking for a while. Just ordered a 780M (pulled from Dell/Alienware) + more RAM + SSD for my mid-2011 27". Will post back with results

look forward to your results mate, with a few people posting good results about it, if it works for you then i might just spring for one. how much did you pay for the 780M? are there different models of it and if so how do i know what I'm looking for, does it need to come from a dell?
[doublepost=1466936448][/doublepost]so, can/should i buy this

http://www.ebay.co.uk/itm/like/2522...52297270758&lgeo=1&vectorid=229508&rmvSB=true


and could i fit it myself or should i pay someone to fit it.

when people say no boot screen, by that you mean i dont get the apple logo and i can't hold down option to get the choice of boot disk, but i can change between discs by using system preferences.

 

[frets]

Do you guys think once MacOS Sierra comes out the GTX780 will still be supported? @MacVidCards @mhafeez ?

 

[flszen]

My Mid-2011 27" iMac's original 2GB Radeon card stopped working last December. I got a replacement of the 1GB Radeon card that the 2011 iMacs shipped with, supposedly new. It stopped working a few weeks ago. Bah. I threw in the towel on ATI/AMD cards and try an Nvidia. I just finished installing a GTX 770M (for Dell/Alienware) that I got used (supposedly "lightly", who knows what that means, lol) from eBay.

I had to grind down part of the heat sink to accommodate some components on the GPU that it was colliding with. (I used a 4" cutoff wheel.) As expected, no boot screen and no brightness control, but it's running like a champ. I have my fingers crossed that it's not something else in the system causing the GPUs to blow.

 

[mhafeez]

Do you guys think once MacOS Sierra comes out the GTX780 will still be supported? @MacVidCards @mhafeez ?

Yes I think so. MacOS Sierra still uses same old nvidia drivers, Netkas has confirmed it.

 

[BleepBloop8234]

So I recently got a 2011 iMac 21.5 for free and am planning an upgrade of the ram and the GPU. I have never taken apart a iMac though and was wondering how hard it is to actually replace the GPU? I am looking at a Dell Nvidia GTX 780m so I know I need that. I saw a guide on iFixit on how to take it apart but figured I would ask people that actually accomplished it on how hard it is. Also was wondering if there was maybe a video guide somewhere or something. Any help would be appreciated as I have read all 20 pages of this thread and you all seem very helpful with this.

 

[bjoroy]

look forward to your results mate, with a few people posting good results about it, if it works for you then i might just spring for one. how much did you pay for the 780M? are there different models of it and if so how do i know what I'm looking for, does it need to come from a dell?

I got this one: http://www.aliexpress.com/item/for-...eForce-GTX-780M-GTX780M-N14E/32563714669.html well, I'm still waiting for it to arrive. Will probably be another week or so I guess. Rest of the parts are here though. Oh, i also got a used i7-2600 (not K, U, S or anything), so I'll try to switch the stock i5-2500S at the same time.

Big question remains though...after: 3x more ram, HDD-> SSD, ATI 512MB -> nVIDIA 4GB, i5 (2,5-3,3ghz) -> i7 (3,3-3,8ghz)... will my wife, who uses the computer, notice any difference? Other than "Hey, the boot logo is gone!"

 

[greenbirdlx]

I have been trying to install the Nvidia Web Driver from their website but I get an error message saying its not compatible on my El Capitan. Is there another place I can get drivers for the GTX780m Nvidia Web Driver? Do we really need the nvidia web driver in any case?

Cheers

I couldn't find a working one by browsing/search their site, but it seems these guys have it all linked up

http://www.insanelymac.com/forum/to...river-updates-for-el-capitan-update-06232016/

I tried cinebench before and after the web drivers, FPS went from 30 to 42!

 

[Synchro3]

Nvidia drivers: http://www.macvidcards.com/drivers.html

 

[BleepBloop8234]

Can anyone tell me if this card would work? http://www.ebay.com/itm/DELL-ALIENW...897790?hash=item5b2727197e:g:rtIAAOSwjXRXZCt2

 

[JPamplin]

Hiya! Did you have to refresh the BIOS? Do you have full support (brightness, external monitors, boot screen, etc.)?

My experience was a resounding success, installing a 780M in my 2011 21.5" i7. I did have to modify the hard drive case a bit, there was an interference with the new card since it is "taller" than the stock card.

I had to omit one of the PCB screws, and sand out a small bit of one of the plastic air dams. If I were to do it again, I'd remove the entire PCB before grinding on the hard drive case and reinstall it after. I used an old shirt to make a pseudo-surgical cover, and vacuumed up any other grinding I could find after.

Booted up in OS X and was good to go, no issues! Installed CUDA drivers just in case. Switched to Bootcamp Windows 10, had a 480p resolution to start, but was able to install drivers and now runs great. Attached are some pics, hopefully they help anyone else.

My source was ebay, bought on June 13, 2016 for $295 shipped.
DELL Alienware M18x M17x Nvidia Geforce GTX 780M 4GB Video Card N14E-GTX-A2 Used
Lot AWDA-GTX780

P.S. I had been lurking this thread for awhile, registered just to document and say thanks to those that tried it and reported back first!

 

[Tazling]

My experience was a resounding success, installing a 780M in my 2011 21.5" i7. ...

My source was ebay, bought on June 13, 2016 for $295 shipped.
DELL Alienware M18x M17x Nvidia Geforce GTX 780M 4GB Video Card N14E-GTX-A2 Used
Lot AWDA-GTX780

You got a deal it seems, I can't find one now for less than $400 on ebay. Seems like resellers have realised that these cards are in demand (rats!).

After reading all 20 pages of the thread I'm still completely undecided as to whether it's worth the risk and hassle to try the upgrade (21.5" 2011 iMac with feeble 512MB Radeon GPU). Pretty intimidating if you are not used to field-stripping iMacs what I take away as executive summary is

1) for best compatibility seek a used card pulled from an Apple product such as Radeon 6970M -- plug and play, if you're lucky. (Though some sources say the card is a bit too large for a comfortable fit and may overheat in the smaller 21.5" case: https://www.ifixit.com/Answers/View/91197/Can+I+install+an+ATI+Radeon+6790+2GB+in+21.5"+iMac).

2) for 2nd best compatibility seek an NVIDIA GTX GeForce series 6xx or 7xx, but you will lose startup screen and brightness control and may have other issues such as overheating, also may have to make physical mods to the internals (cut away plastic, adjust mounting positions etc)

3) handle your mobo connections VERY carefully!

4) use higher quality heatsink paste

So I think being chicken-hearted and new to surgery on iMacs I would choose option 1 if I do go for it.

Many thanks to all posters who shared their successes (and fails)... brave pioneers all.

 

[AdamRealMacMods]

Hey guys and girls. I run RealMacMods.com, and have been dealing quite deeply into MXM cards for another project.

I wonder if i can help you out with the problems you still have with the upgrades.

If interested, please let me know what remains to be done, and i will contribute how i can.

 

[Backwardscire]

Just incase anyone was looking for some stuff, decided to sell off my late 2009 iMac and the Apple 6970M 1GB that I had purchased to upgrade it.

6970M with thermal paste kit:
http://www.ebay.com/itm/Apple-iMac-...826764?hash=item2caf50274c:g:f~4AAOSwyKxXg6Zc

iMac:
http://www.ebay.com/itm/Apple-iMac-...440231?hash=item2caf4a4167:g:4KAAAOSwRgJXgtN2

 

[Lost Heaven]

Encouraged by the feedback given by @mhafeez and @Fl0r!an, I was finally able to replace my defective 6970M with a Dell 780M pulled from an Alienware machine with the same VBIOS that has been reported as working (80.04.af.00.03).

After installing the current version of the Nvidia Web Driver on an up to date 10.11.5 El Capitan, I can't get the iMac's internal screen to work. Everything else seems to be working: OSX detects the 780M and works perfectly on an external display, Screen Share or Airplay.

Windows also detects the card and works fine with the external display or Remote Access.

I've made some benchmarks and can confirm huge improvements on either OS, which leads me to believe there's no problem with the GPU and that it is correctly installed.
Neither OS seems to recognise the 27-inch internal display. OSX sees it as being a 23-inch display with a single resolution of 1280 x 1024.

Windows sees it as a generic PnP display.

I've checked and double checked that all the LCD's cables (VSync, LVDS, power and backlight) are correctly plugged in to the logic board and inverter board.
What could be happening? Does anyone who had black screen issues with their 780M had the same symptoms?
Is it possible that I somehow damaged the LCD or any of the cables? I handled everything with care and can't see any noticeable damage on the cables. I ran out of ideas and I'm at a loss on how to diagnose what's happening. Does anyone have a clue? It's the same card, same brand, pulled from the same system, with the same VBIOS as the ones other members have been reporting working.

Off topic: just noticed @MacVidCards got suspended. That's a huge blow to anyone who has been following this thread hoping for any custom ROM solutions for our problems.

 

[Fl0r!an]

Can you attach the VBIOS here? I'd like to have a look at it.

 

[Lost Heaven]

Can you attach the VBIOS here? I'd like to have a look at it.

Sure thing, here you go. What do you make of it?

Update: I just tried turning the system on without the LCD connected, and OSX shows the exact same generic 23-inch generic display under display settings, so I can now assume it's something related to it. It's not being detected at all. Other than a faulty cable or the inverter board, is there anything else about it that could have malfunctioned?

 

[Fl0r!an]

Thanks. It's 100% identical to the VBIOS I already had on my computer, which was supposed to work fine in an iMac. DCB table is also looking fine, 1st connector is LVDS, others are DP, so I can't tell what's wrong here.

Maybe doublecheck that the card is seated perfectly? Although I doubt that this is your issue here...
Can you PM me an IOReg dump? I'd like to tell on which port the system thinks you have that ghost monitor attached. ioreg -l -w0 -p IODeviceTree > dump.txt would be sufficient.

 

[Lost Heaven]

I shall in a few minutes, have the machine disassembled at the moment. Tried booting it while monitoring the diagnose LEDs and noticed that only the 1st and 2nd light up. The fact that the 4th LED doesn't light up should confirm an issue with the connection to the LCD, but I'm surprised that the 3rd one is off too. If the system is functioning perfectly when connected to an external display, and the GPU is working, as confirmed by the benchmarks and the noticeable performance gains, why would the 3rd LED be off? And how could it not be seated perfectly and still work like this?

 

[Fl0r!an]

I've received the IOReg dump, the graphics related portion is attached at the bottom of this post.
You can see that it defined a total of 4 ports, and none of them has a display attached (is this correct? No external display used during IOReg dump?).

I've never seen those entries before:

    | | | +-o LCD@fffff  <class IORegistryEntry, id 0x100000190, retain 4>
    | | | |   {
    | | | |     "acpi-device" = "IOACPIPlatformDevice is not serializable"
    | | | |     "acpi-path" = "IOACPIPlane:/_SB/PCI0@0/P0P2@10000/GFX0@0/LCD@fffff"
    | | | |   }
    | | | |   
    | | | +-o LCD1@a420  <class IORegistryEntry, id 0x100000191, retain 4>
    | | | |   {
    | | | |     "acpi-device" = "IOACPIPlatformDevice is not serializable"
    | | | |     "acpi-path" = "IOACPIPlane:/_SB/PCI0@0/P0P2@10000/GFX0@0/LCD1@a420"
    | | | |   }

This might be your ghost monitor, don't know who created that...
Besides that it's looking like a correctly init'ed GPU to me.

So I read some old posts in this thread and found two success stories which confused me a lot:
https://forums.macrumors.com/threads/2011-imac-graphics-card-upgrade.1596614/page-20#post-23040957
https://forums.macrumors.com/threads/2011-imac-graphics-card-upgrade.1596614/page-7#post-21267443

Both state that the internal display is connected via (e)DisplayPort. Huh? I was quite sure that the 2011 iMac was using LVDS. The first connector in your GTX780M ROM is LVDS, so if the internal panel actually expects a DP signal I'm not surprised this isn't working. But it shouldn't work for anyone else...

I couldn't find a definitely working GTX780M BIOS in this thread though, would like to compare them...

    | | +-o GFX0@0  <class IOPCIDevice, id 0x10000018f, registered, matched, active, busy 0 (58 ms), retain 29>
    | | | | {
    | | | |   "acpi-device" = "IOACPIPlatformDevice is not serializable"
    | | | |   "NVDA,noEFI" = <"true">
    | | | |   "assigned-addresses" = <1000018200000000000000b00000000000000001140001c20f0000000000008000000000000000101c0001c20f00000000000090000000000000000224000181000000000020000000000000800000003000018200000000000000b10000000000000800>
    | | | |   "class-code" = <00000300>
    | | | |   "subsystem-vendor-id" = <28100000>
    | | | |   "vendor-id" = <de100000>
    | | | |   "hda-gfx" = <"onboard-1">
    | | | |   "IOPCIExpressLinkCapabilities" = 4537603
    | | | |   "IOName" = "display"
    | | | |   "NVArch" = "GK100"
    | | | |   "IOPCIPMCSState" = 0
    | | | |   "IOPCIMSIMode" = Yes
    | | | |   "VRAM,totalsize" = <0000f0ff>
    | | | |   "rom-revision" = <"VBIOS 80.04.af.00.03">
    | | | |   "com-master-varp" = <00c056f580ffffff>
    | | | |   "IOChildIndex" = 1
    | | | |   "pcidebug" = "1:0:0"
    | | | |   "IOPCIExpressLinkStatus" = 4354
    | | | |   "pci-aspm-default" = 0
    | | | |   "NVCLASS" = "NVDA"
    | | | |   "IOInterruptControllers" = ("io-apic-0","IOPCIMessagedInterruptController")
    | | | |   "NVCAP" = <050000000000ffffffff00000000000e00000000>
    | | | |   "IOPCIExpressCapabilities" = 2
    | | | |   "built-in" = <00>
    | | | |   "IOPCIResourced" = Yes
    | | | |   "IODeviceMemory" = (({"address"=2952790016,"length"=16777216}),({"address"=66571993088,"length"=268435456}),({"address"=66840428544,"length"=33554432}),"IOSubMemoryDescriptor is not serializable",({"address"=2969567232,"length"=524288}))
    | | | |   "IOPowerManagement" = {"ChildrenPowerState"=2,"CurrentPowerState"=2,"CapabilityFlags"=258,"ChildProxyPowerState"=2,"MaxPowerState"=3}
    | | | |   "NVDA,accel-loaded" = <01000000>
    | | | |   "saved-config" = <0f084c0110000000070000000000000f02800000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000ff00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000>
    | | | |   "name" = <"display">
    | | | |   "subsystem-id" = <10000000>
    | | | |   "AAPL,ndrv-dev" = Yes
    | | | |   "rm_board_number" = <00000000>
    | | | |   "model" = <"NVIDIA GeForce GTX 780M">
    | | | |   "IOPMIsPowerManaged" = Yes
    | | | |   "VRAM,totalMB" = <ff0f0000>
    | | | |   "device_type" = <"NVDA,Parent">
    | | | |   "compatible" = <"pci1028,5aa","pci10de,119f","pciclass,030000","GFX0">
    | | | |   "vbios-revision" = <0300af0480>
    | | | |   "IOHibernateState" = <00000000>
    | | | |   "NVDA,Features" = <00080000>
    | | | |   "NVDAType" = "Web"
    | | | |   "attached-gpu-control-path" = "IOService:/AppleACPIPlatformExpert/PCI0@0/AppleACPIPCI/P0P2@1/IOPP/GFX0@0/NVDA,Display-A@0/NVDA/AGPM"
    | | | |   "IOReportLegendPublic" = Yes
    | | | |   "IONVRAMProperty" = Yes
    | | | |   "reg" = <0000010000000000000000000000000000000000100001020000000000000000000000000000000114000142000000000000000000000000000000101c0001420000000000000000000000000000000224000101000000000000000000000000800000003000010200000000000000000000000000000800>
    | | | |   "IOReportLegend" = ({"IOReportGroupName"="Interrupt Statistics (by index)","IOReportChannels"=((5291294645182070784,4295098369,"               First Level Interrupt Handler Count"),(5291294645182070785,4295098369,"              Second Level Interrupt Handler Count"),(5291294645182070786,4295098369,"        First Level Interrupt Handler Time (MATUs)"),(5291294645182070787,4295098369,"   Second Level Interrupt Handler CPU Time (MATUs)"),(5291294645182070788,4295098369,"Second Level Interrupt Handler System Time (MATUs)")),"IOReportChannelInfo"={"IOReportChannelUnit"=0},"IOReportSubGroupName"="GFX0 1"})
    | | | |   "device-id" = <9f110000>
    | | | |   "revision-id" = <a2000000>
    | | | |   "IOInterruptSpecifiers" = (<1000000007000000>,<0200000000000100>)
    | | | |   "NVDAinitgl_created" = "yes"
    | | | |   "acpi-path" = "IOACPIPlane:/_SB/PCI0@0/P0P2@10000/GFX0@0"
    | | | | }
    | | | |
    | | | +-o LCD@fffff  <class IORegistryEntry, id 0x100000190, retain 4>
    | | | |   {
    | | | |     "acpi-device" = "IOACPIPlatformDevice is not serializable"
    | | | |     "acpi-path" = "IOACPIPlane:/_SB/PCI0@0/P0P2@10000/GFX0@0/LCD@fffff"
    | | | |   }
    | | | |   
    | | | +-o LCD1@a420  <class IORegistryEntry, id 0x100000191, retain 4>
    | | | |   {
    | | | |     "acpi-device" = "IOACPIPlatformDevice is not serializable"
    | | | |     "acpi-path" = "IOACPIPlane:/_SB/PCI0@0/P0P2@10000/GFX0@0/LCD1@a420"
    | | | |   }
    | | | |   
    | | | +-o NVDA,Display-A@0  <class IONDRVDevice, id 0x10000033d, registered, matched, active, busy 0 (15 ms), retain 8>
    | | | |   {
    | | | |     "display-connect-flags" = <00000000>
    | | | |     "compatible" = <"NVDA,NVMac">
    | | | |     "IOFBDependentIndex" = 0
    | | | |     "nativeNDRV" = <"advn">
    | | | |     "AAPL,RegEntryID" = <607a0e00000000009f85f1ffffffffff656d6953000000007a6c755200000000>
    | | | |     "AAPL,ndrv-dev" = Yes
    | | | |     "IODeviceMemory" = (({"address"=2952790016,"length"=16777216}),({"address"=66571993088,"length"=268435456}),({"address"=66840428544,"length"=33554432}),"IOSubMemoryDescriptor is not serializable",({"address"=2969567232,"length"=524288}))
    | | | |     "IOFBDependentID" = 4294967695
    | | | |     "AAPL,gray-page" = <01000000>
    | | | |     "device_type" = <"display">
    | | | |     "NVDA,DeviceClass" = <80000000>
    | | | |     "NVDA,SubDeviceClass" = <80200000>
    | | | |     "display-cfg" = <ffffffff>
    | | | |     "AAPL,gray-value" = <bfbfbf00>
    | | | |     "noNVRAM" = <01000000>
    | | | |     "name" = <"NVDA,Display-A">
    | | | |     "port-number" = <00000000>
    | | | |   }
    | | | |   
    | | | +-o NVDA,Display-B@1  <class IONDRVDevice, id 0x10000033e, registered, matched, active, busy 0 (6 ms), retain 8>
    | | | |   {
    | | | |     "display-connect-flags" = <00000000>
    | | | |     "compatible" = <"NVDA,NVMac">
    | | | |     "IOFBDependentIndex" = 1
    | | | |     "nativeNDRV" = <"advn">
    | | | |     "AAPL,RegEntryID" = <40f60a0000000000bf09f5ffffffffff656d6953000000007a6c755200000000>
    | | | |     "AAPL,ndrv-dev" = Yes
    | | | |     "IODeviceMemory" = (({"address"=2952790016,"length"=16777216}),({"address"=66571993088,"length"=268435456}),({"address"=66840428544,"length"=33554432}),"IOSubMemoryDescriptor is not serializable",({"address"=2969567232,"length"=524288}))
    | | | |     "IOFBDependentID" = 4294967695
    | | | |     "AAPL,gray-page" = <01000000>
    | | | |     "device_type" = <"display">
    | | | |     "NVDA,DeviceClass" = <80000000>
    | | | |     "NVDA,SubDeviceClass" = <80200000>
    | | | |     "display-cfg" = <ffffffff>
    | | | |     "AAPL,gray-value" = <bfbfbf00>
    | | | |     "noNVRAM" = <01000000>
    | | | |     "name" = <"NVDA,Display-B">
    | | | |     "port-number" = <04000000>
    | | | |   }
    | | | |   
    | | | +-o NVDA,Display-C@2  <class IONDRVDevice, id 0x10000033f, registered, matched, active, busy 0 (1 ms), retain 8>
    | | | |   {
    | | | |     "display-connect-flags" = <00000000>
    | | | |     "compatible" = <"NVDA,NVMac">
    | | | |     "IOFBDependentIndex" = 2
    | | | |     "nativeNDRV" = <"advn">
    | | | |     "AAPL,RegEntryID" = <e0720500000000001f8dfaffffffffff656d6953000000007a6c755200000000>
    | | | |     "AAPL,ndrv-dev" = Yes
    | | | |     "IODeviceMemory" = (({"address"=2952790016,"length"=16777216}),({"address"=66571993088,"length"=268435456}),({"address"=66840428544,"length"=33554432}),"IOSubMemoryDescriptor is not serializable",({"address"=2969567232,"length"=524288}))
    | | | |     "IOFBDependentID" = 4294967695
    | | | |     "AAPL,gray-page" = <01000000>
    | | | |     "device_type" = <"display">
    | | | |     "NVDA,DeviceClass" = <80000000>
    | | | |     "NVDA,SubDeviceClass" = <80200000>
    | | | |     "display-cfg" = <ffffffff>
    | | | |     "AAPL,gray-value" = <bfbfbf00>
    | | | |     "noNVRAM" = <01000000>
    | | | |     "name" = <"NVDA,Display-C">
    | | | |     "port-number" = <05000000>
    | | | |   }
    | | | |   
    | | | +-o NVDA,Display-D@3  <class IONDRVDevice, id 0x100000340, registered, matched, active, busy 0 (0 ms), retain 8>
    | | |     {
    | | |       "display-connect-flags" = <00000000>
    | | |       "compatible" = <"NVDA,NVMac">
    | | |       "IOFBDependentIndex" = 3
    | | |       "nativeNDRV" = <"advn">
    | | |       "AAPL,RegEntryID" = <20edddfeffffffffdf12220100000000656d6953000000007a6c755200000000>
    | | |       "AAPL,ndrv-dev" = Yes
    | | |       "IODeviceMemory" = (({"address"=2952790016,"length"=16777216}),({"address"=66571993088,"length"=268435456}),({"address"=66840428544,"length"=33554432}),"IOSubMemoryDescriptor is not serializable",({"address"=2969567232,"length"=524288}))
    | | |       "IOFBDependentID" = 4294967695
    | | |       "AAPL,gray-page" = <01000000>
    | | |       "device_type" = <"display">
    | | |       "NVDA,DeviceClass" = <80000000>
    | | |       "NVDA,SubDeviceClass" = <80200000>
    | | |       "display-cfg" = <ffffffff>
    | | |       "AAPL,gray-value" = <bfbfbf00>
    | | |       "noNVRAM" = <01000000>
    | | |       "name" = <"NVDA,Display-D">
    | | |       "port-number" = <07000000>
    | | |     }

 

[TheMrDen]

Hi , sorry for the translation , I use google translate, I have a imac 27 2009. Can I install hd6970 or gtx660m from dell alienware? Will it work like the original from apple?

 

[Lost Heaven]

(... No external display used during IOReg dump?).

You're correct: I had the external monitor disconnected at the time of the dump and was accessing the system via Screen Sharing.

Both state that the internal display is connected via (e)DisplayPort. Huh? I was quite sure that the 2011 iMac was using LVDS.

I was under the same assumption, and LVDS is mentioned pretty much everywhere, even when referring to the cable (http://www.applemacparts.co.uk/stor...nium-lvds-display-cable-mid-2011-p-78252.html). Apple, however, does mention DisplayPort in their Technician Guide:

I ended up running out of ideas on how to further troubleshoot the undetected internal display and ordered this very same cable. I'm hoping either this or the inverter board is the culprit, even though I find it annoying that I handled the disassembly with such care and still it would become damaged. You really have to handle flex cables as if you are attempting a circumcision...

On a side-note, while playing around with the system using the external display, I ran into another issue: as I mentioned, I made a series of benchmarks to measure the performance gains from the 6970M, and noticed a very obvious improvement. Just a few minutes ago, to give an example, I ran Tomb Raider's (2013) in-game benchmark. The best result I ever had with the 6970M was 37 fps. The 780M produced 55 fps. That's an exact 50% boost which, by my standards, is pretty impressive.
However, while monitoring temperatures and clocks with GPU-Z, I noticed that, even under heavy loads, the software showed the core clock does not change and remains at 324 MHz at all times. Dell's 780M default core clock is 771 MHz. I downloaded Nvidia Inspector, to troubleshoot if GPU-Z was misreading this, but got the same reading:

Notice that the GPU Load at the time of this screenshot was 97%, as I had a benchmark running at the same time, and the Current Clock sits at 324 MHz. At this point, it should throttle to an higher clock. It seems it's stuck at the P5 state at all times. Also, notice that the PCIe interface is reported as being 3.0 but it's always running at 2.0. This also explains why, even after a solid hour of heavy GPU load, the 780M's temperature has never went beyond the 70 ºC mark.
Installing an older driver didn't fix this. I made sure to check, under the Power management mode tab of Nvidia's Control Panel, that Prefer maximum performance is enabled. I also disabled Link State Power Management under the PCI Express tab of Windows' Power Options.
I've read reports of other locked 780Ms that required flashing a custom VBIOS to circumvent this, but I wonder why others with the same card and BIOS don't seem to have any problem. I'm going to wait until the cable arrives before I even consider tinkering with the VBIOS.

I'm still somewhat amazed that a severely underclocked 780M, locked at less than half its default clocks, performs on average 50% faster than a fully functional 6970M