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Agilato

macrumors newbie
Original poster
Jun 5, 2020
26
1
Will i7 9700f work in 2019 iMac 27"?

So i was researching this question and found few successful i7 9700 upgrades but nothing about F version of a CPU.
Over all it's pretty much same as regular 9700 just without built in Intel Graphics.
I were not able to find mentioning Intel GPU in any iMac info, so my guess that iMac micro-code just disable it anyway.

Also i was interested how loud iMac with: i7 9700 or i7 8700, compare to i5 8500.

Thanks.
 

Agilato

macrumors newbie
Original poster
Jun 5, 2020
26
1
Initially i installed regular i7 8700 65W and computer sometimes kick in fan to cool it, but over all it's quiet.
After I installed i9-9900KF and it worked fine, so i think i7 9700F will work also with no issues.

Intel i9 9900KF has similar temps as i7 even it's 95W in long term load Apple limits it to 85W which makes this cpu work on heavy load with fan working quiet at 85(C) and 1200RMP, longer load - higer temps we get, it's able to sustain long time at 95(C) with fan around 1400-1600.

Edit:
- Please read whole topic! KF CPUs have some limitations related to iGPU and some instructions shortage!
 
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Topsithebig

macrumors newbie
Oct 24, 2020
9
4
Initially i installed regular i7 8700 65W and computer sometimes kick in fan to cool it, but over all it's quiet.
After I installed i9-9900KF and it worked fine, so i think i7 9700F will work also with no issues.

Intel i9 9900KF has similar temps as i7 even it's 95W in long term load Apple limits it to 85W which makes this cpu work on heavy load with fan working quiet at 85(C) and 1200RMP, longer load - higer temps we get, it's able to sustain long time at 95(C) with fan around 1400-1600.
I'm from Brazil and I really liked your video, and I had already done this procedure on an imac 2017, this year I took a 2019 and did the same procedure as yours! my question is that i used the sidecar with an imac, and after this upgrade it does not appear on the screen on my ipad, now i don't know if it was an update to ipados14 or if due to the fact that the kf does not have a video, and can give something , have you done this test?
 
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Topsithebig

macrumors newbie
Oct 24, 2020
9
4
I also noticed that it takes a while to turn on, sometimes I have to press the power button some 3x, and some apps like photoshop and illutrator he chokes on heavy images, in video editing, he was fantastic
 

Agilato

macrumors newbie
Original poster
Jun 5, 2020
26
1
I also noticed that it takes a while to turn on, sometimes I have to press the power button some 3x, and some apps like photoshop and illutrator he chokes on heavy images, in video editing, he was fantastic
I haven't tried Sidecar.
Over all i don't have any issues you mentioned, v been testing it for last 2 months.
It does turning slightly slower(~5sec) than my 2017 iMac, but i had same load speed with stock i5 8500.
Also i founds some bits of info that Apple uses KF CPUs in some of their machines.
I have seen reports about chocking and turning issues only on cheap Chinese "F" versions of i9 non "KF" one.
Are you sure you have "KF" one?
 
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Topsithebig

macrumors newbie
Oct 24, 2020
9
4
I haven't tried Sidecar.
Over all i don't have any issues you mentioned, v been testing it for last 2 months.
It does turning slightly slower(~5sec) than my 2017 iMac, but i had same load speed with stock i5 8500.
Also i founds some bits of info that Apple uses KF CPUs in some of their machines.
I have seen reports about chocking and turning issues only on cheap Chinese "F" versions of i9 non "KF" one.
Are you sure you have "KF" one?
yes mine and kf, and I found it a bit strange that sometimes it takes a long time to connect, and the sidecar doesn’t work on my ipad pro, it even moves on the screen, but the ipad screen is black, something else what I noticed was that when iso the illutrator and photoshop, he chokes, something that didn't happen on my imac 2017 i7
 
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Agilato

macrumors newbie
Original poster
Jun 5, 2020
26
1
Have you tried to reset PRAM and SMC?
Also install fresh system.
What kind of SSD you use? May be problem is in SSD not in CPU?
 

Topsithebig

macrumors newbie
Oct 24, 2020
9
4
Have you tried to reset PRAM and SMC?
Also install fresh system.
What kind of SSD you use? May be problem is in SSD not in CPU?

I believe it is not the ssd, because I had installed it before on the ssd that comes on the imac, and then I did the installation on the ssd that I put and the same happens, I found it strange because even the sidecar I used it is not showing up, there I don't know if it's the case with the i9 9900kf or the ipadOs update
 
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Topsithebig

macrumors newbie
Oct 24, 2020
9
4
I had the opportunity to test an i9 9900k, to my surprise it worked perfect with sidecar, so the question was that he wanted to use the integrated video of the processor, now I have another question, I think that because it is a processor that requires more power it Sometimes the imac doesn’t turn on at first, I have to connect at least 4x until it gives a screen, and it has power because the external ssd indicator light is always on when pressing the power button
 

Agilato

macrumors newbie
Original poster
Jun 5, 2020
26
1
I had the opportunity to test an i9 9900k, to my surprise it worked perfect with sidecar, so the question was that he wanted to use the integrated video of the processor, now I have another question, I think that because it is a processor that requires more power it Sometimes the imac doesn’t turn on at first, I have to connect at least 4x until it gives a screen, and it has power because the external ssd indicator light is always on when pressing the power button
Have you used K cpu in your iMac?
I still think, what if problem in motherboard revision, not in CPU...
There is no difference in K and KF power consumption... at least by Intel's documentation...
And i don't have issues... at least i haven't check sidecar (doesn't have compatible device)
 

Topsithebig

macrumors newbie
Oct 24, 2020
9
4
Have you used K cpu in your iMac?
I still think, what if problem in motherboard revision, not in CPU...
There is no difference in K and KF power consumption... at least by Intel's documentation...
And i don't have issues... at least i haven't check sidecar (doesn't have compatible device)
I don't think I explained my whole situation, my imac it had an i5 9600k, so I upgraded to an i9 9900kf, where all my doubts happened, because the Sidecar didn't work, it was a black screen on the iPad, and to connect the imac he wasn’t at first, he had to try a few times to be able to connect, and I noticed that there was power, because when I put an external SSD and turned on the power button, I turned on the SSD light, but nothing on the screen, so I took one another i9 but now a 9900k, and the Sidecar works perfectly, but I still have a delay in turning the imac on, I don’t know the power, I doubt if the source provides enough power for the imac to turn on first
 
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Agilato

macrumors newbie
Original poster
Jun 5, 2020
26
1
One critical question: Do you have 21 or 27 iMac?
21inch doesn't support CPUs with TDP higer than 65W
Tho i5 9600k has 95W i don't think it spikes to 120W as i9
May be you right about power delivery system or mb your problems might be related to bent pins on the socket.
Also check your RAM, i had issue with my iMac when replaced ram it was not starting correctly,
i pulled it out then put it back and it start working, bad contact or something.
 

Topsithebig

macrumors newbie
Oct 24, 2020
9
4
One critical question: Do you have 21 or 27 iMac?
21inch doesn't support CPUs with TDP higer than 65W
Tho i5 9600k has 95W i don't think it spikes to 120W as i9
May be you right about power delivery system or mb your problems might be related to bent pins on the socket.
Also check your RAM, i had issue with my iMac when replaced ram it was not starting correctly,
i pulled it out then put it back and it start working, bad contact or something.
hello, then mine is 27, I believe it is not crooked pins because I checked to see if everything was okay, and they were ok, and also if I thought they wouldn't even work, and it works just takes a while, and as if it was expensive with a lack of battery ha ha ha, i've seen some reports of this problem in some even without doing any kind of upgrade
 

Agilato

macrumors newbie
Original poster
Jun 5, 2020
26
1
I had 2015 iMac 27inch that sometimes wasn't turning-on at all.
One pin on the connector which connects Logic-board to Power Supply got loose(soldering joint got broken)
Accidentally spotted it when was inserting the cable back in.
I soldered it back-in and worked perfectly fine after that.
 

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GoodWheaties

macrumors 6502a
Jul 8, 2015
761
801
Yeah the reason the F model CPUs will have issues is they don’t have integrated graphics. Apple is using that for certain functions like Sidecar and some other apps. Best to stick with models that include integrated graphics for full compatibility.

wait a minute. Apple DOES use KF models in some iMacs. Huh I thought for sure they didnt. Never mind, must be something else going on.
 
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Agilato

macrumors newbie
Original poster
Jun 5, 2020
26
1
Yeah the reason the F model CPUs will have issues is they don’t have integrated graphics. Apple is using that for certain functions like Sidecar and some other apps. Best to stick with models that include integrated graphics for full compatibility.

Other than Sidecar do you know any other software or tool that i can check my KF with.
I haven't sealed my iMac yet and have regular i9 9900k in my Gaming PC so i can swap.
Now it's just challenge for me to see =)
 

Agilato

macrumors newbie
Original poster
Jun 5, 2020
26
1
Before swapping my CPU i checked all devices thru the terminal to see if Intel GPU is presented,
i wasn't able to spot any traces of iGPU in to the system device list.
It actually was main reason why i picked i9 KF, got a very good deal on it.
 
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GoodWheaties

macrumors 6502a
Jul 8, 2015
761
801
I’m not really sure now. I thought Sidecar was used exclusively with the integrated graphics but it must not be the case. Is Apple whitelisting processors or would it have to do with which GPU you have?
 

Agilato

macrumors newbie
Original poster
Jun 5, 2020
26
1
I’m not really sure now. I thought Sidecar was used exclusively with the integrated graphics but it must not be the case. Is Apple whitelisting processors or would it have to do with which GPU you have?
I just used MacCPUID by Intel to check the info. Radeon Pro 570X 4 GB.
Also Here is topic about KF and K a lot of interesting info.
Looks like people confused if they actually use i9 9900K or KF one
May be it's depend on revision?
 

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Topsithebig

macrumors newbie
Oct 24, 2020
9
4
I had 2015 iMac 27inch that sometimes wasn't turning-on at all.
One pin on the connector which connects Logic-board to Power Supply got loose(soldering joint got broken)
Accidentally spotted it when was inserting the cable back in.
I soldered it back-in and worked perfectly fine after that.
and it can be too, but I won't touch it for now, since I put the screen on, I'll just let it rest when I'm not using it, but thank you very much my friend
 

Agilato

macrumors newbie
Original poster
Jun 5, 2020
26
1
Got myself 9.7inch iPad Pro, first thing i test was sidecar and it WAS NOT WORKING!

So i just finished swapping i9-9900KF with i9-9900K and sidecar started to work fine.

Topsithebig - Thanks for your feedback all this made difference for me.

 
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