twice in the last few weeks my intel imac has acted strangely,
a few weeks ago i returned home after a weekend away and turned it on, nothing happened but the sleep LED flashed very quickly (several times per second) i shut it down and tried again no good. i removed my logitech mouse and tried again and it was fine, (it may have just been the bumping of some cord at the back that fixed it.) i reset the SMC and it has been good for a few weeks, though it doesnt really turn off it just sleeps normally!
today the misses switched users and the screen stayed blue, she turned it off and on and it didnt boot properly, just went to a blue screen again apparently. i turned it off and on again but this time the sleep led flashed slowly. tried again and it worked.
i have added a kingmax 512 sodimm months ago but have had no prior probs,
to me it seems like a memory error but what do the flashing led codes mean, the slow flash means ram apparently. i swapped around the memory modules and ill see how it acts. ill be trying to turn it off more now
if it plays up again ill remove the kingmax module.
anyone had any similar probs turning on their imac if it has been off for a while??
any help appreciated, cheers

take it back to the stock config (ie as you bought it home) and work your way back up. it smells like bad memory..