화면은 나오는데 더 이상 진행되지 않습니다.

방금 보드를 분리하여 memory를 완전히 분리한 뒤 테스트 해봐도

같은 증상 입니다.

어떤 문제가 있는 것일까요?

⟐ Commented 5월 05, 2022 at 22:44 GMT-7

When I connected an external VGA monitor, I saw it did boot to the “No boot device” screen, which was expected since the original HDD was removed due to failure.

Eventually a MacOS install CD got stuck, so I opened it up and removed it manually. After that, the behavior changed. It now chimes with the green power LED, then as the external monitor briefly detects a signal, it shuts off.

If I try again right after, the power LED comes on but nothing else happens. No chime, no video, nothing until I power it off manually. After unplugging for a few seconds and plugging back in, it goes back to the initial state where it chimes and then shuts off when it should show video on both CRT and external display.

What can I do? I replaced the PRAM battery and it made no difference. It also shuts off before I can do a PRAM reset (Opt+Cmd+P+R), and the physical PRAM button hasn’t helped either.

Trickle voltages seem normal, but when it reaches the “power LED only” state, the down-converter board trickle voltages are lower than normal.

I can also hear the high-voltage crackling as it powers off, so I assume the CRT is receiving power in some way. One other thing of note is that either the speakers, or the down converter board make a high pitched sound, I'll attempt to identify the source later today.

⟐ Commented 5월 19, 2026 at 3:45 GMT-7

As a disclaimer, I know this may be a hardware issue and that is why I am here. I have already taken it to Apple and they had no luck, telling me it needs a logic board replacement. It wasn't worth the money so this has turned into just a slow learning project that I've been chipping away at as a hobby.

I have tried to restore it with Apple Configurator and another MacBook, but after putting it into DFU mode and waiting for it to restore, it fails with this error (4014)

Unexpected device state 'DFU' expected 'RestoreOS' (Probably forced into DFU mode externally)

AC recognizes the Mac Mini, and the restore works up until Step 4/4, "Installing System", where it pauses halfway and then gives that error.

At that point I can see via the status light on the Mac Mini that it goes from a normal boot (white) to DFU mode again (solid amber) randomly, and AC sort of flickers at this point as well and then complains about the Mac Mini being in DFU (instead of RestoreOS).

I guess this could be something fried on the board, but I wouldn't know where to start because the only apparent issue being that it just randomly dips out of RestoreOS and back to DFU is very odd.

I've heard this error (4014) can be a faulty cable, but I've tried a lot of different ones, including a genuine Apple USB-C cable. I may buy a brand new one and try again.

Do you know of any software or hardware issues this could be? It seems like a simple issue but with no real rhyme or reason to it. Even if you just have a hunch, any tips on where I should look next would be greatly appreciated.

⟐ Answer accepted 5월 18, 2026 at 15:16 GMT-7

⟐ Commented 5월 11, 2026 at 7:45 GMT-7

I am planning to upgrade my iMac (27 inch - mid2010) which is now 10 years old and running on El Capitan 10.11.6 OS. Since its having a good CPU (i7 2.93) I am considering replacing the stock HDD (1TB) to an SSD, and maximising the RAM from 8GB to 32GB.

1. is this upgrade worth it? and will I notice a different when using it?
2. for the RAM upgrade, I think this part is the best option (iMac Intel 27" (Core i5 or i7) EMC 2390 (Mid 2010) Memory Maxxer RAM Upgrade Kit)?
3. for the SSD, I was reviewing this guide (Mac Intel 27" EMC 2390 Hard Drive Replacement), and I am confused about the parts options. the SSD Upgrade Bundle with Crucial MX500 SSD 1TB, or buying 2 TB SSD Segate Hybrid 3.5" Hard Drive with all the required tools separately which will almost cost the same. my concerns are:
   • is the two SSD mentioned having the same performance?
   • is the two SSD mentioned having the same certification with my iMac?
   • is there any drawback for using Segate 2TB over Crucial 1TB?

**

This is my first time upgrading my iMac, and I really appreciate if you can guide me in selecting the best parts to get the most performance out of it for the longest period.

Regards,

⟐ Answered 5월 07, 2026 at 22:33 GMT-7

⟐ Answer accepted 5월 02, 2026 at 17:40 GMT-7

⟐ Answered 5월 02, 2026 at 11:48 GMT-7

First, sorry for the hiatus. I've been out of the business for a while. But I'm back!

Apple couldn't tell me anything. They offered me to pay a flat $500 fee, and they would replace anything that needed to be replaced untill it worked…

I ended up just selling it for parts…

So I have a Apple Mac Pro "Quad Core" 3.7 (Late 2013) that wont power on.

I do not know the history of the machine.

I plugged it in and got nothing, no beeps. no fan spinning, no response.

I do all the normal procedures, swapped ram, tried different SSD, reset SMC, tried different power cable and outlet. None of that worked.

I took the case off and found a bright red LED shinning.

So I started searching the internet, thinking that there MUST be some information about this red LED.... NOTHING!!!

So I proceeded to take the whole thing apart, took it down to bare bones to make sure everything was connected properly and to see if I could find any corrosion from any liquid damage or such.

While I was at it I re applied thermal paste on both the CPU and GPU.

Nothing appeared to be out of place, no damage to the board, all connections were secure.

I put it back together, powered it on, and still nothing, just the red LED...

WHAT IS WRONG WITH THIS THING!?

Please, if you have any idea what could be wrong, any suggestions, or any explanation about this red LED I would LOVE to hear it.

I'm totally baffled by this one...

Thanks in advanced,

Taylor

⟐ Answered 5월 02, 2026 at 5:18 GMT-7

I got horizontal lines over the display! During the warranty period they replaced the board ( it blacked out ) and now this is happening. They refused to replace the device saying out of warranty and asked to replace it :-|. They were not even sure that changing the display will fix the issue. I am hesitant to replace the screen as I am better off to buy a new one rather keep repairing the faulty product.

Is there any way to fix it?

Tried
- Reinstall the OS
- External Display = Works fine
- Reseating those 3 cables

Lines kind of flickers, may be some lose cables?

Please help

⟐ Commented 5월 02, 2026 at 0:54 GMT-7

⟐ Commented 5월 01, 2026 at 15:24 GMT-7

Somehow I completely forgot that Apple ever made a discrete GPU Mac mini. Having realized that, I looked up GPU benchmarks and found that the 6630m GPU is kind of decent. Many times mower powerful than the 320m that came before it, or the Intel HD 4000 that came after it. Based on benchmarking the 6630m vs the minimum GPU system requirements for GTA4, I should be able to play that game on it too!

Those are the specs. Now here's the reality. The mini's GPU runs really good for half a minute or so? Then the fan in the mini maxes out, and the GPU throttles so bad, the framerate tanks. IN FACT, its so bad, that I had to dial back the graphics settings in GTA San Andreas to MATCH what I play on the nVidia 320m!!! So on a Mac with over 3x the GPU performance, I'm effectively getting the exact same amount of real-world performance.

My first thought was, Windows 10 must be broken, I should revert to Windows 7!
But after continued use, I'm not sure that's the issue. The second most obvious problem might be bad thermal paste? I know that replacing thermal paste on Macs is all the rage these days, but its not usually as effective as "reddit" would make it seem. But that said, I am in a case where I'm trying to max this machine out. So maybe its worth while to pop off the heat sink, clean it all down, and put some fresh paste on it? If I do go this route, is it worth buying some fancy kind of paste, or will any new, unopened paste be fine?

Any other thoughts on what might be going on? I would be very happy if I could use this mini to play GTA:SA at full native 1080p, and if I could play GTA4 at any decent, playable graphics level.

⟐ Commented 4월 28, 2026 at 5:04 GMT-7

⟐ Commented 4월 26, 2026 at 19:06 GMT-7

⟐ Answered 4월 25, 2026 at 5:55 GMT-7

the ribbon is so fragile, looks like it broke

thanks

After changing the microphone for a new one it is still the same problem, no idea what happened, i was being very careful inserting the flex cable on the board.. when removing the original one i pulled it instead of removing the tiny latch because i did not know

Any idea?

Thanks

⟐ Answer accepted 4월 20, 2026 at 15:15 GMT-7

I have a late 2013 27" that I replaced the failing HDD with a new 2TB Crucial Bx500 SSD.

Write speeds are an abysmal 20-40MB/s no mattter what.

I have also replaced the SATA cable AND enabled Trim.

I have tried also formatting the drive to exFat and then back to APFS with a clean install of Catalina, and then migrated the data again with migration assistant.

Originally, I thought the drive or cable was bad, so I replaced both again.

The issue persists. Write speeds hover from 20-40 MB/s.

Thank you for your consideration and help. I will be sure to respond as promptly as possible.

⟐ Commented 4월 19, 2026 at 12:09 GMT-7

⟐ Commented 4월 16, 2026 at 7:05 GMT-7

⟐ Commented 4월 10, 2026 at 20:06 GMT-7

⟐ Answer edited 4월 08, 2026 at 11:16 GMT-7