iMac 2017 27" nightmare

[dermoid777*]

So I think I killed my iMac....

Its an 2017 A1419 27 inch

it came with i5 3.8GHz - I wanted to upgrade to an i7-7700, plus 1TB nvme

Got all the parts, watched all the videos

Big day comes - have al my fixit instructions printed out, go through it step by step, have my screws and parts labels all laid out

Opened the screen w/ the fixit cutter wheel - OK done - all adhesive came off OK and was careful with the 2 monitor cables

So took all the items out step by step

down to the logic board

lets just say no video prepared me for the fact that whilst it's really hard to unscrew all 4 CPU screws and all 4 GPU screws, it's downright impossible to put those back without moving the CPU, keeping tension constant and keeping the tension springs held down - you are tightening 4 x screws on either side of the board at the same time - insane - you need 3 pairs of hands!!!

I did my best anyway through a combination of tape, plastic ties and lying on the floor and screwing in from bottom...!

so put it all back together

Did it start up? No Effin way - not a whimper out of it

OK! So take apart again

down to logic board

and yes CPU had moved and was bent at corner

put back in and tried ot power on again - NOPE
so could be the i7 too - bummer
but now of course i am sh___ing it that i damaged the pins

SO - put the original i5 in again
Started with power and fan on full power
but no further


SO looked at pins

yes some bent , one twisted - tried my best to straighten
Put i5 back in - again no boot

SO Logic Board is screw*d

OK - well I need this badly back up and running so bi the bullet and ordered the board from reputable returnable company in UK the book yard. The price is ... a lot. Then add customs and UPS delivery and its €560 - oh my god, cant afford it but got it anyway

so came yesterday - put RAM in, put bluetooth board on, reinstalled , connected the PSU and was getting 4 diagnostic LED's - great
Then connected screen - power on and....

... no chime, no screen
... look behind screen and LEDs go to 4 (with 4 being half-lit)

try connect keyboard and PRAM reset - nothing
try SMC reset - nothing

screen is black and dead

I know - now I am thinking its the screen but try external display thunderbolt 3 to hdmi on 4K external - and nothing !

and its not chiming either .... which to me is weird

I replaced the PRAM battery
and reseated / tried different configurations of RAM while it was on - nope - no differrence

Could it be the hard drive ?
It has the stock NVME that it came with

Booting while holding Cmd-R does nothing

Kind of at wits end now .... could it be something shorted on logic board?
Its new and seems to be coming from a reputable source...

It just powers on, fans go to full speed, 4 LED's all light and nothing... so now I'm thinking have broken original logic board, new logic board AND a screen... 🙄😟 I mean that takes some doing. Not happy with myself to say the least. This machine is for my work as a freelancer and I've basically cost myself a huge amount of money I can't afford. Luckily there's no work / data on it but still.... just feel like an idiot.

Anyone ever seen this where you have 4 LED's and no chime / no OS boot...?

ALL help suggestions welcome !

 

[Nguyen Duc Hieu]

Buy another working iMac and DO NOT open it ever.

 

[wilberforce]

Buy another working iMac and DO NOT open it ever.

If that is what Hieu says, who is experienced and helpful in repairing iMacs, I think you are in trouble, unfortunately

 

[dermoid777*]

If that is what Hieu says, who is experienced and helpful in repairing iMacs, I think you are in trouble, unfortunately

Thanks for taking the time to reply - would that I could buy a new one. So the lesson is never try.

 

[rpmurray]

Actually, the lesson should: Don't try unless you have a backup machine. I normally don't try to do these kinds of upgrades unless the followng conditions are met:

1. It is out of warranty.
2. I've just bought a new computer so the one I'm working on is now a spare and won't affect me if things go wrong.
3. Upgrading just one part at a time. Test after each upgrade. You're just looking for trouble if you try to jump ahead and do everything at once.

Disclaimer: I have sometimes been known to ignore step one when I get impatient and allow my desires to overrule my reason.

 

[Fishrrman]

Time to start shopping for a replacement.

And a hint:
DON'T try to open and "upgrade" the next one...

 

[wilberforce]

Thanks for taking the time to reply - would that I could buy a new one. So the lesson is never try.

I don't think the lesson is never try ( although I get the quote). I try lots of repairs to all sorts of things myself, and occasionally screw up, which is OK.

I think the lesson is to consider the downside, i.e., what you have to lose, the chance of losing it, and be prepared to accept the loss (i.e., be mentally and financially able to buy a replacement if it goes horribly wrong.)

Another trap is spending more and more to fix it. At some point you are throwing good money after bad, and instead just have to cut your losses and quit.

If there is little to lose and lots to gain, then go for it.

 

[ThrowerGB]

I don't think the lesson is never try. I try lots of repairs to all sorts of things myself, and occasionally screw up, which is OK.

I think the lesson is to consider the downside, i.e., what you have to lose, the chance of losing it, and be prepared to accept the loss (i.e., be mentally and financially able to buy a replacement if it goes horribly wrong.)

Another trap is spending more and more to fix it. At some point you are throwing good money after bad, and instead just have to cut your losses and quit.

If there is little to lose and lots to gain, then go for it.

And don't forget the cardinal rule. BACKUP - BACKUP - BACKUP. Make suer you have a backup of ALL of your system before starting any repair. I fact, make two and keep them in different places.

 

[T Coma]

Buy another working iMac and DO NOT open it ever.

Peak MR.

“I can’t answer your question / help you out in your current situation, but I can tell you what you should have done, or (in case you can’t travel back in time) give purchasing advice like money isn’t a thing.”

 

[wilberforce]

nvm

 

[GloatGoat]

Peak MR.

“I can’t answer your question / help you out in your current situation, but I can tell you what you should have done, or (in case you can’t travel back in time) give purchasing advice like money isn’t a thing.”

You may want to check out Hieu's many helpful posts on MR, he has more experience tinkering with Mac's than most. He gave the OP sage advice, sometimes it's best to cut your losses.

 

[dermoid777*]

Thanks for the replies - Yeah I can see now that I should have been more prepared to accept the consequences I suppose. I think the reason why I thought it was possible was b/c I used to open macs and upgrade them all the time however that was on Intel Mac Pro's / older models - I wasn't ready how irreversible it was going to be and unfortunately no youtube video really will show you that. Will keep trying to get it fixed but as you say good money after bad is an issue.. thanks again for responses though

 

[macguru9999]

well, just talking generally now. you definitely killed the first mobo so unless you could straighten the pins its gone. what about the second one ? did you take care of the pins on that ? did you seat the processor correctly ? did you try both processors ? though i guess if you seated it wrong then that means more bent pins ! and dont blame the screen, an imac will boot and chime with no screen attached so its not that ...

 

[NC_Bulldog]

Anyone ever seen this where you have 4 LED's and no chime / no OS boot...?

ALL help suggestions welcome !

I have done several successful iMac upgrades not involving a CPU upgrade. However, I pretty much duplicated your experience with a recent iMac CPU upgrade because of that very difficult to reinstall CPU retainer bracket.

I also bent the CPU pins and had to replace the MB and CPU. Fortunately in the end I was able to bend the pins back and get the original MB to work. Along the way I also managed to damage the big connector between the LCD and MB. Fortunately it was about $15 to replace it.

With the four lights on and no boot chime I would consider a possible problem with the RAM or SSD. The iMac checks those first, I think, before the LCD turns on. With the SSD on the underside of the MB it is time consuming to easily access it so try changing the RAM around first. Even try just one stick. If it's not the RAM, then the next culprit is the SSD.

Good luck. I know how you feel!

 

[dermoid777*]

well, just talking generally now. you definitely killed the first mobo so unless you could straighten the pins its gone. what about the second one ? did you take care of the pins on that ? did you seat the processor correctly ? did you try both processors ? though i guess if you seated it wrong then that means more bent pins ! and dont blame the screen, an imac will boot and chime with no screen attached so its not that ...

Thanks for that - for the second motherboard CPU/GPU was included so did not have to go near the sockets - just reinstalled in the iMac. Hmm .. if the iMac will boot and chime w/no screen then i'm not sure why it won't boot... I have power and fan spin but that's all even when connected to external display.

 

[dermoid777*]

I have done several successful iMac upgrades not involving a CPU upgrade. However, I pretty much duplicated your experience with a recent iMac CPU upgrade because of that very difficult to reinstall CPU retainer bracket.

I also bent the CPU pins and had to replace the MB and CPU. Fortunately in the end I was able to bend the pins back and get the original MB to work. Along the way I also managed to damage the big connector between the LCD and MB. Fortunately it was about $15 to replace it.

With the four lights on and no boot chime I would consider a possible problem with the RAM or SSD. The iMac checks those first, I think, before the LCD turns on. With the SSD on the underside of the MB it is time consuming to easily access it so try changing the RAM around first. Even try just one stick. If it's not the RAM, then the next culprit is the SSD.

Good luck. I know how you feel!

Thank you so much - it's really helps to hear other people have been through this!

So yeah I thought the SSD / RAM night be the issue too - Using the replacement undamaged Logic Board I put the original NVME back in, reseated the RAM using the stock iMac RAM that came w/the machine.. tried just 1 stick... tried in ports 1 and 3 only... no go on any of these.

I've got some tentative assurance from a logic board repair place in the UK that they can fix the pins on the original board so have my fingers & toes crossed there ...

I have actually returned the replacement "working" Logic Board now ... if the repair guy cannot fix then putting further money in would be unwise .. I mean the reason that I wanted the CPU upgrade in was because I was fairly unimpressed w/ the speed of the i5 cpu... I have a 2014 MBPro (i7 4770) and it honestly seems faster than that 2017 iMac sometimes ... ! 🤷🏻‍♂️

It's true you have the 5K screen (and thats main reason for buying ) ... however if that also needs repair/replacement (though would be great if it's just a damaged LCD cable) surely would be best put that money into a M1 MBPro.... even if I get refund cleared I have still lost €150 on customs charges/UPS so far and it will be another €200 I would say to repair the original board... so it's al mounting up.

The only consolation is that the iMac was a great deal when I bought it.. but I seem to be paying for that now... cuh.

Thanks again for the replies.

 

[rpmurray]

“I can’t answer your question / help you out in your current situation, but I can tell you what you should have done, or (in case you can’t travel back in time) give purchasing advice like money isn’t a thing.”

You make that sound like it's a bad thing.

It's like that brand new 14TB spinner I bought a few months back that I had all formatted and ready to go and then accidentally knocked it off a table. I knew as soon as I heard it hit the floor that it was a goner. Being stubborn, overoptimistic and a masochist I went ahead and tested it and confirmed that I was an idiot. I'm just recounting that here so people can get some amusement from my misfortune.