Can i add a nvidia GTX 765m Graphic card on to a 2374 emc IMAC 27 inch (late 2009) ? ?

SUCCESS! I have indeed succeeded at this quest. I got the Nvidia Geforce GTX 765M from a deceased Clevo laptop and finally succeeded in getting it running in my mid-2011 27-inch Imac a couple of days ago (after letting the whole project sit for a few months). I believe that the recent Nvidia drivers included in Sierra 10.12.3 are what made it possible. Of course, I get no boot screen, brightness control or second monitor support but at least the card is running. I have made enquiries, at appropriate websites, to see if an Apple EFI ROM can be flashed into this card thereby (hopefully) alleviating the aforementioned problems. If anyone wants more info, please let me know.

I was wondering if you pr amyone else had had any success with this endeavour (or something close to it). I have a 2011 Imac 27 with a misbehaving ATI GPU which is beyond the 4 year window for free replacement. I have lucked into an Nvidia Geforce 765m from a Clevo laptop and am hoping to do the switch. I have extensive experience working on Imacs and have no peoblem doing the physical replacement (although it is time-consuming). I also have extensive experience installing and EFI-flashing PC video cards (8800GT, Radeon HD 5770 and 5870 and, my most recent flash, an Nvidia GTX 680) into various Mac Pros. I am therefore fully aware that I will probably (at least at first) lose my boot screen, brigjtness control and 2nd monitor support. I am posting here to know three things:

1- Has anyone tried/done a similar swap?

2- Is there an EFI ROM that I could flash onto this card (probably using nvflash from a CMD window through Windows 7 via Bootcamp)?

Please respond only if you know what you are talking about. I have seen too many self-proclaimed "Mac experts" on this site spout drivel such as: "All Imac video cards are soldered to the motherboards" or "Apple uses proprietary video card interfaces." Or the ubiquitous "Take it to the Genius Bar." Puh-leeze!

After having said all that (and possibly sounding like a complete a**hole), any help would be greatly appreciated.

Looks like the Late 2012 iMac's video card is on the logic board.

So I would think "no" to a swap with a late 2009 27".

However, any 5 series or 6 series with 512 ram or greater will work, and be better.

5670M, 5750M, 6750M, 6770M, or 6970M.

(You will need the heat sink, too.)

Look at School or local government surplus property auctions, even if they are dead, you can salvage parts.

https://www.govdeals.com/index.cfm?fa=Main.AdvSearchResultsNew&kWord=iMac&whichF orm=vehicle&searchPg=Main&rowCount=10&St…

For reports by people who have made similar swaps start here: https://forums.macrumors.com/threads/2011-imac-graphics-card-upgrade.1596614/

1. Disclaimer: I have not attempted such a swap myself and would not recommend the average user try this at home.

That's awesome, man! I've recently starting thinking of swapping a laptop graphics card in a 2010 iMac. It's cool to see Sierra support the card. If I may ask, what do you mean by "no boot screen"? I'm also looking to swap out the CPU. I fix up Macs at a local shop but I haven't ventured into upgrading beyond "Recommended Items".

I was able to switch out an i7 processor from a mid 2010 iMac to another mid 2010 iMac (originally i5). I also have swapped out graphics cards of the Radeon 256MB and 512MB variety, but, like you, I'm looking to use something more powerful. When you swapped the laptop graphics card and installed it with the appropriate heatsink, was there any issue of start up? Did anything need to be modified (BIOS, OS, etc)?

Again, pretty cool, man. Pretty cool.

Hi. Well, I hope that I can help you out. First of all, let me tell you that I have no training in all of this. I have a toolkit and I know that Google is my friend. Other than that, I write down what I do to take stuff apart and then just follow the steps backwards...

Anyway, the no boot issue is that, with a video card that does not have an Apple ROM flashed to it, there is no grey screen with the darker Apple logo during boot up. After the boot chime, the screen stays black during the entire boot process until the Finder (or login screen if you have not enabled automatic login) appears. Why is this an issue? Well, in the event that your hard drive goes South, usual practice is to hold down the Option key before the boot chime to be able to select another volume (usually the Recovery partition) to boot into. Well, without a boot screen, you can't do that. I am not 100% certain, however, if it is that the screen is not there or if it is just that you can't see it. If it is the latter, you could possible navigate to the other boot volume "in the blind". If, for example, you know that the icon for the Recovery partition should be the second icon from the left, you could press and hold the Option key for a certain amount of time after the boot chime, then, when the hard drive had settled down, you could press the right arrow key once and then the Return key and, in theory, you would expect the system to boot into that startup volume. Testing this theory out would just entail a little trial and error and should be doable rather quickly. I just haven't taken the time to try it yet. Other than that, no brightness control (I use a nifty little utility called Brightness Slider which is available for free at the App Store) and no second monitor support (haven't figured out a Macguiver for that yet), it works beautifully. Of course, if the good people over at Netkas figured out a way to modify the ROM from a GTX 755m or 775m (both of which are used on 2013 Imacs), we could possibly flash that ROM to the card and that should fix all of the problems. Heck, you might even be able to flash the card with the ROM from one of those two cards as-is and it might work... or you might brick the card... and that is not a risk I am willing to take.

While you seem to be looking for better performance, what drove me to try this Frankenupgrade was pure economics. The stock card (Radeon 6970m) had died. I took the Imac to the Apple Store and they quoted me the completely ridiculous price of $735 to replace it. Resellers know this and I couldn't find an Apple MXM card with similar power on the used market for less that $500 (with currency exchange, shipping, Customs fees, etc.). So, when I ran into this card locally from a deceased Clevo laptop for fifty bucks as-is (because it couldn't be easily tested), I figured it was worth the risk.

As far as startup problems, there really weren't any. I just had to make sure that I was running Sierra 10.12.3 (apparently only that latest update has the correct video drivers). Also, I reset the SMC and PRAM before starting up. Remember that, after such a radical hardware modification, first boot may take longer than usual, leave the system enough time to boot. (I left the room and made myself a coffee.) When I returned, I had a big beautiful 2560X1440 desktop staring me in the face. Yes!

So, if you have more questions, please do not hesitate to ask. Either way, please let me know how it goes if you decide to do it. Finally, if any of the smart people who may read this have figured out a way to flash an Apple ROM to this video card, please share it.

In response to ANM7373:

Hi there. If you look earlier in this thread, you will see that I have indeed installed a 765m into a 2011 Imac 27. When I tried my setup with Sierra, it was very finicky about upgrades. When I updated to the second or third last update to Sierra, I too lost my screen and could only access the computer through screen sharing (which I had luckily enabled before). I recall that the only resolution available was 1280 X 870 (or something like that). I had cloned the hard drive before doing the update so I was able to restore things using CCC.

Fast forward to this October and High Sierra. I let an external SSD update to High Sierrra; no Nvidia web drivers and no other extra steps. I set the Imac to boot from that drive (again with screen sharing enabled) and...

Bingo! No fuss, no muss, it booted right up and gave me a standard desktop after not giving me a boot screen. (You know that you won't get a boot screen, right?)

So, my suggestion to you, is that you take some precautions (have an external backup and set up screen sharing) and try High Sierra. If you have any luck (as I did), you will be successful.

i need professional answers

Please be careful what demands you make here. You have found a user-to-user forum. Not too many "professionals" around and Apple does not respond here. So you will get talented amateurs who enjoy helping other Mac users. If that condition works for you, let us know. Otherwise we'll need to invite you to search for a "professional site" on your own.

Fair enough. I've been doing this for about 15 years, if that's OK with you.

This site:

https://www.ifixit.com/Guide/iMac+Intel+27-Inch+EMC+2309+or+2374+Graphics+Card+R eplacement/9553

describes in step-by-step illustrated format how to do exactly what you ask. However, the larger issue is getting the more powerful video card itself. Apple uses a proprietary design and you cannot simply get an "off-the shelf" video card that will work. Apple does not sell replacement cards except for in-store repair, so you are looking for a discontinued, high-end card that has been pulled from a 2011 iMac. The source for a pulled card shown in the article wants US$600 for the card alone!

Considering your computer is already classes as "obsolete" by Apple, you may wish to cost-analyze your project to make sure you aren't better off getting a newer iMac with the card you want already installed. Otherwise, I believe the article I linked has everything you need to attempt the conversion.

Regards,

Allan

My understanding is that, as the logic boards are custom-fitted to one brand of card, you must replace the cards in kind. The MacTracker database shows only AMD Radeon cards fitted to the 2009 iMacs.

The iFixit site has user forums where you may find more people who are into serious modding and are doing more complex conversions. Certainly may be worth a visit.

One little correction, the late 2009 iMac isn't on Apples obsolete list. It's not even considered vintage yet according to this document Vintage and obsolete products - Apple Support

That said I don't think I'll be spending $600 on mine 😁

Not likely.....but you can try. Apple stores aren't in the upgrade business, when they replace something it's almost always with a like kind part.