Delidded CPU, now no video

Hardware CPU
1

Okay, I have scared myself. I decided to delid my i7-7700k for the obvious reasons. I had a particularly ‘warm’ chip that wasn’t overclocking well, so it made the decision easier. I got the Rockit delidder and followed instructions. The process seemed to go very well and I reinstalled the processor. Visually, the motherboard appears to boot normally in that all the pretty lights flash as usual, fans spin and no odd beeping noises. But, I had no video output from my GPU.

I pulled the cable from the GPU and plugged directly into the motherboard to try the integrated graphics. Same behavior, unfortunately.

So far I have pulled out the GPU, reset the CMOS and reseated the RAM. I checked around for any random loose connections, but my cable management is pretty decent. I doubted anything got knocked loose and didn’t find anything.

While I guess it’s possible that I completely forked the CPU, I don’t think things would be look so normal in other ways. At least that’s what I’m hoping…

Anybody have any ideas? I feel like I’m overlooking something obvious and my nervousness is stopping me from seeing it.

I7-7700k, Asus Strix Z270e, Asus GTX1080TI, 16gb Ram, NZXT Kraken X62

2

Did you re-attach the IHS when you delidded the cpu? Did you use liquid metal or did you use traditional thermal paste between the IHS and the die?

3

Sorry to be late getting back. I used liquid metal as included in the kit. And I reattached the lid with gasket maker (hi temp)

4

You may have shorted out some components with the liquid metal then. Best not power up the CPU anymore until you’ve checked.

5

liquid metal gets hard… very hard… you practially have to catch it on fire (use a heat gun for a few minutes) to seperate the ihs again.

6

How long does it take to harden?

7

Not sure you’d have to look at the details on the packaging/online all I know is once it cures it’s basically solder and requires a ton of heat. Getting to it sooner would be better than later and I would still use heat even if the cure time isn’t done.

8

I have heard the opposite, interesting you say that. I have a couple tubes of liquid ultra and one tube of conductonaut lying around; perhaps I should test.

I have, however, heard that LU cures some while conductonaut doesn’t (mostly)

9

maybe i’m thinking of something else by mistake? i could have swore liquid metal was the one that hardens like solder.

10

You’re confusing it with some cold welding compound, I guess. Liquid metal stays liquid.

11

LOL! Did you check your display input setting?
Power cycle the display?
Try a different display?
Verify that the display works with a different system?

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12

I was thinking the same thing. I always question why no one uses kapton tape to cover the components around the chip die.

13

I tested all of the above

14

Gamers Nexus used nail polish; Sounds even better

1 Like
15

take the cpu apart again and clean off any liquid metal that spilled off the cpu die and then coat everything around the die with nail polish. it will protect the cpu from further spill offs. hopefully the damage isnt too bad and will work.

1 Like
16

A plan. Going to do this this afternoon. I will report back.

17

That was the only option I could imagine.

18

BIOS Reset jumper?

19

Covering the socket Interposer PCB (the Green CPU board) with insulation when dealing with Liquid metal is really really really important. Almost as important as making sure that the IHS is perfectly level ontop of the CPU die. (if it isn’t you can crack it due to the CPU cooler pressure).

It cannot be stated enough times. Plenty of people have killed their CPU’s like this.

In the i7-7700k’s case there are 4 diagnostic test points on the top of the interposer that can be shorted or alternatively overflow from liquid metal itself can create enough capacitance through the PCB trace coating to mess up the delicate signal timings.

Always cover your socket Interposer board with kapton tape / nail polish when applying liquid metal.

2 Likes
20

(OP here) Update!

I dropped the 7700k into a test bed mobo that I set up with a spare B250.
The CPU is fine and posts normally. Yay for that. Delidding went ok after all.

But I somehow bent some socket pins in the Z270 board while working with it. 100% on me. I was lazy and didn’t want to completely remove the radiator on my AIO cooler. I sort of held it out of the way with one hand while I worked with the other. I assume I ‘bumped’ the socket at some point.

I will try to straighten them, but I don’t expect much. I’ll test with the Pentium jus in case I think it’s usable.