Imac 27 inch 2011 grey screen after boot

[USB3foriMac]

Referring to point 1....disconnect HDD put back together then retry? you mean try with stick or internet recovery when HDD is disconnected?

Yes

Point 2....bake GPU,what temp,how long and this may sound daft what position in the oven? top shelf,middle etc or does this not make a difference.

Many different oppinions about this, a web search will give you many options to choose from. I believe it was also mentioned in this thread. Preheat to 200 degC, then put in card for some time. I use 6 min, many use 8, and others use 10. Seems not to matter too much, and my reasoning is: the shorter the time, the less stress on the other components (such as the tantalum caps).

Point 3....that would take money which is in short supply unless i can find an SSD pretty cheap.
Thanks for the help,much appreciated

You can get 256GB for nearly nothing, second hand of course. And if you can successfully bake the GPU, you will feel a huge difference when you use the machine with SSD.

 

[UK2011mac]

Yes

Many different oppinions about this, a web search will give you many options to choose from. I believe it was also mentioned in this thread. Preheat to 200 degC, then put in card for some time. I use 6 min, many use 8, and others use 10. Seems not to matter too much, and my reasoning is: the shorter the time, the less stress on the other components (such as the tantalum caps).

You can get 256GB for nearly nothing, second hand of course. And if you can successfully bake the GPU, you will feel a huge difference when you use the machine with SSD.

Thanks for the info i am going to try this,this coming weekend,Need to get the 27inch going as the 2009 is to slow ha ha