REPAIR SERVICE - iMac 24in Nvidia 8800GS Graphics Card Reflow
This is a repair service that is performed on our premises. Once booked you will need to either bring or send your machine into us, or you can have us send our courier to collect it - see here. Once complete you can collect the machine from us, or we can ship it back to you for our standard courier delivery charge (applied during the checkout process).
This service is an attempt at a reflow repair of the graphics chip on an iMac. Machines that commonly have these faults are white and aluminium 24" models from around 2007/2008 with the Nvidia 8800GS graphics chip, although other models can develop them. Please be aware that while the initial success of the procedure is very high, its longevity varies. See below for more details.
Distorted video on screen, which is replicated on an external screen.
No video, but the machine boots and adjusting the volume up/down makes noise.
In some cases, the machine won't turn on at all - which can be caused by this problem, but may be a symptom of an unrelated logic board error.
Cause of the problem:
The solder used to attach the graphics cards to the logic board in these machines is subject to dry / bad joints in the connections.
What is reflowing?
Reflowing is the use of controlled direct heat to the graphics chip in order to melt the solder and repair these dry joints and return the card to a working state. This is achieved using infra red pre-heating plates and direct hot air soldering stations with fine temperature control. The logic board is removed from the machine, the heatsink and old thermal paste removed and cleaned and the board examined. The board is then heat treated as described. The board is left to cool before reassembly and reapplication of thermal paste. A period of GPU intensive testing is then run to test the machine.
Does the reflow work in every case?
It depends on the machine.
The nature of the fault means that sometimes the graphics chip has shorted out and cannot be successfully reflowed - this is most likely in machines that will not turn on at all.
In machines where the machine boots but there is distortion or no graphics at all (but the machine responds to volume up/down requests) the likelihood of success is very high. Our current success rate on these type of machines is over 95%.
How long will the repair last?
We have machines that, at the time of writing, have been going strong for over 18 months after a reflow. We have also had a number that have failed some months down the line. It is not a complete fix and the underlying fault with the machine remains. To be cautious, we suggest thinking of the procedure as purchasing additional time for the machine.
What if the reflow is unsuccessful?
In the unlikely event of the reflow being outright unsuccessful, we will refund you half the cost of the work (this refund excludes any delivery/collection charges).
If the fault recurs within 3 months of work being completed, we will offer you a choice of a further free reflow, or the same 50% refund.
If it fails outside of 3 months we offer a further reflow attempt at half price, but with no further warranty.
There is an article on the MacUpgrades.co.uk blog with more details on the reflow procedure.
Below is a list of compatible Macs for this item. You can click on any of the pictures to see the precise models it covers. We guarantee full compatibility with all models covered by each link, subject to any exceptions explicitly listed below.
iMac 2007 - Mid 2009
- For the 2008 24" model with the Nvidia 8800GS graphics card.