Any ides why it won't start


A month ago my iMac 27" i7, 2Gb late 2012 hade a problem with its GPU (different color vertical lines all over the screen). I called apple support and they told me that i hade to replace the whole logic board (since the GPU is solder to the Logic board). I went online an bought a new logic board for a late 2013 iMac 27" i7 2GB, i missed that it was sold without a CPU.

Therefore i bought a CPU at a local store (Intel core i7-4790K, LGA1150) original is a (Intel Core i7 4771 LGA1150)

When i started putting everything tougher i realized that the SSD i hade from my late 2012 would not fit my late 2013 logic board. But i kept going. I assembled the whole mac (without a SSD).

When i connected the mac and pushed the power button nothing happened (i could hear the main hard drive spinning) but the screen would´t come on and there was no "turn on" sound.

Why do you think my iMac won't start

1. The new late 2013 logic board won't work with the other late 2012 parts (screen, etc)?

2. The logic board won't power the new (Intel i7 4790K) CPU correctly, should i buy the original (intel Core i7 4771)?

3. It won't start cause its missing the SDD (I believe that you can order a iMac without a SSD)

iMac was sold without a SSD

"*This model has a Serial ATA (6 Gb/s) connector for a 3.5" hard drive as well as a proprietary PCIe connector for an SSD. If the SSD is not installed at the time of purchase, the connector still is present and later professional or self-installation is possible."

已回答! View the answer 我也有这个问题


按维修分数 0


Get a couple of answers on this before spending any more money.


所有超过US$100.00或包含 Pro Tech工具包的订单免费送货!



与 #ImAGenius 分享您的维修故事


与 #ImAGenius 分享您的维修故事



Go here and enter the serial number (from the bottom of your stand) to see if the new board is even compatible. Since you know the GPU is the issue I would do a search for a company with a good reputation with a rework station. All you may nee is a $100 re-ball service or GPU replacement. That new board is not cheap, or if it is, be very wary of it.


按维修分数 3

My bet would be the CPU. The machine may not support the 4970K. If you can, find a CPU that originally came with the logic board and try that. If it doesn't work, then you might have a bad logic board.


按维修分数 3


thx alot i will buy a new intel Core i7 4771 tomorrow, so u agree that the ssd is not necessary for the imac to work properly?


Dear jakobk,

I have the same issue, but slightly different.

I started with a 2013 system. for reasons that are explained here I changed the CPU for the 4790. Mine too won't boot up.

So I have a new CPU and a new mother board and it still won't boot.

I'm interested in your progress, what you eventually did and if you confirmed the lack of compatibility with the CPU.


按维修分数 0


jakobk 将永远感激不已

过去的24小时: 0

过去的7天: 0

过去的30天: 7

总计 285