While it is possible to replace the Graphic's chip in some models, it varies from model to model because many are soldered directly onto the logic board. Plus even if it were possible to replace/upgrade your model 1) it would have to be the same chip configuration and 2) Apple does not provide the firmware for upgrading.
The 2 most highly recommended third party RAM vendors are OWC and Crucial.
I purchased 16 gbs from OWC.
As for the video card, OWC has the 5750 in stock. http://eshop.macsales.com/item/Apple/6615578/ Given that the description states it's compatible for the late 2009 27" models, the chip config should match right?
Can you please also elaborate on the firmware you mentioned? I supposed I would only need to replace the card and install the given drivers.
The video card of the iMacs cannot be upgraded. What you see is what you get. Of course, you or someone else can take it apart, unsolder the chip, and resolder the newer one but there is still no guarantee it will work. How much faith do you have in yourself or the other person that the job will be successful? If you have the extended warranty, it will be voided. As far as ram is concerned, you can do it yourself. Apple describes how to. Why do you want to upgrade the video card? If it's for your work, then you bought the wrong computer.
Actually, the posts that state it can't be done are WRONG! And it does NOT require
any soldering or chip removal for the 27" iMacs.
I have the exact same late 2009 27" iMac, and upgraded it to the part from
OWC the you pointed out previously, this one:
You'll be voiding your warranty certainly, but unless you have Apple care you're already
past Apple's 1yr anyway...
It is absolutely possible, and works great. You do not need to touch any firmware, and OS X
already has the drivers for this board. It's entirely a hardware process to upgrade it, i.e. open
the iMac and replace the board and you're done.
The process of upgrading it isn't particularly trivial, but it is absolutely possible, I've been using
the upgraded 5750 1GB board since last Fall (~October) without a single problem in my 27"
High level summary of steps, (there are better more detailed instructions a few places online like iFixit)
(1) remove display cover panel
(2) remove display itself, look online for the details this part can be dicey
(3) disconnect all cables from logic board, tape back near where they came from to get them out of the way and make them easy to reconnect
(4) remove RAM (makes it easier to remove logic board from housing)
(5) unscrew and remove logic board (which has MXM slotted video board attached to it)
(6) set logic board flat on a static safe area
(7) unscrew MXM video board heat sink screws that connect it to logic board, and disconnect it from the logic board
(8) plug in the upgrade/replacement video board
(9) put everything back together
(10) enjoy your faster video card
If you haven't taken your iMac apart before, expect to spend ~90min if you're careful about everything.
If you have, it can be done in ~30-45min.
A couple additional tips, one above was the removing RAM makes it easier to remove the logic board, another
is that when you reinsert the logic board, have a USB cable or similar handy to plug into the back to help
align the logic board when you re-seat it. The last tip is the one about taping the wires back just above where
they get plugged in. I didn't do this the first time through, and one fell down and didn't get plugged back in on
re-assembly. I had to disassemble the whole thing again to dig it out and plug it back in...
It's noticeable for things that require more GPU horsepower, but for day to day usage, not really.
Since the new iMacs were just announced (the ones with thunderbolt), I'd personally wait to see if
OWC puts up some of the 6970M 2GB boards at some point in the next couple months, or even
some of the lower end parts from these newest iMacs.
It's still the exact same daughter board based on the tear downs from iFixit and others, so should work unless the older logic board won't support them for some reason. OWC will say which iMacs they're compatible with if/when they list them for sale.
I asked one of my nerd friends at work and explained what I had and what I wanted to do...they said I wouldnt really even notice the upgrade...so in the words of someone else that posted... looks like we just got the wrong computer for the job...
save your pennies and upgrade or sell your soul to apple and take out a line of credit.
and for that price tag, its a total joke...
But I guess the joke is on us.