Ok kind of a long story but here it goes. I purchased a refurbished 27-inch iMac about a year and a half ago. From out of the box I had issues with it freezing and using lots of ram, upwards of 16-20gb of ram. I was on the phone weekly for months with applecare trying to get this fixed. Nothing worked. At one point while on the phone with a senior tech my screen started flashing from black to normal. So I brought it into our Applestore for them to find the problem and fix this. Mind you this was after over 14 calls to Applecare. Each call lasting anywhere from 1 hr to 5 hrs. Upon dropping off the iMac the "genius" and myself looked over the iMac for any damage before signing off for repair. It was flawless condition. We both agreed on the condition and off it went. 3 days goes by and they call me and tell me my iMac is FINALLY repaired and ready to go. I head to the store that night and out walks a kid with my iMac. I was shocked it was flithy covered in dirty finger prints and black smudges. I look over the iMac and notice the stand has several deep scratches in it. I got the attention of the same "genius" who checked it in. He looked at it said "Ya they will wipe off" he tries to wipe off the stand, but the scratches are to deep. So he just walks off. I flag him down again and he says "Well I can't say we did those or you just did those" and once again just turns and walks off. So not wanting to make a scene I loaded it back into its box and home it went. Next morning I called the store manager and explained what happened he agreed to order me a new stand. Not a good visit. So a few days goes by and I finally get a free night to try out my fixed iMac. Turn it on and what do you know SAME PROBLEM! So I call Applecare and request a screen share to show them the iMac was failing. So we spend another several hours trying everything under sun to find problem. He finally thinks it is me upgrading to Mavricks and wants to send me a snow leopard disk. He also thinks my logic board is failing and tells me he can set up a in house repair so I don't have to drag iMac back to the mall. Mind you this is the 18th tech I spoke to and the first to agree they have in house repair, all other techs told me they don't have that. Anyhow I agree and he tells me he will send a snow leopard disk and call me back to set up in house logic board repair on Monday. This was on Fri. So Monday nothing, tues nothing, weds nothing. Finally thurs I call them, typical applecare Ive been told over and over they will call me back but never do to follow up. So now I have a new tech because after leaving message with original tech he never calls back after 7 hours, so got a new tech. Also forgot to add I did a test myself to try and find problem. I installed my Lacie little big disk as my boot drive with Mavrick, annnnnnnd no problems. Works perfect no issues. So obviously it is the internal HDD. I get the new tech tell him the situation and how I'am tired of dealing with the lack of service and followup. I told him about the external Lacie hdd working flawlessly as my boot now with no ram issues or freezing. He is baffled and says he still wants to change the logic board leave my interal HDD in and see what happens. Kinda a waste of time. So he tells me I should have heard from the in house tech people, they are a private company. Well I haven't heard a thing. Now he wants me to wait even longer for them to call. Now remember this computer has been down for over a year and I have documented 24 calls to AppleCare, also 3 visits to the Applestore all together all with it failing. I'am beyond frustrated. The tech tells me it will be at least 2-3 weeks until they will instal the logic board, then if that doesn't work will be another 2-3 weeks to schedule and change HDD. This isn't even considering the flashing screen I get on occasion which is probably the video card. So now Iam about half through my AppleCare warranty and still have a broken iMac unless I run on a external. I feel they are just pushing this out so I run out of warranty and then go "Oooooh sorry your out of warranty" Then Im stuck with a $2000 paper weight. Anyone else gone through something like this? I think Apple should stop jerking me around and take this doomed iMac back and they can deal with it on their own dime and time and exchange it out for a working iMac. A year and a half without it getting fixed is ridiculously long time. Anyhow just thought I would share and maybe someone here can guide me in the right direction to get this working. Any advice would be helpful because Iam at a loss with Apple.