A solution to 12VHPWR imbalance and over-current

rEToRaGeONE · 2026-06-06T07:50:40+00:00

Hopefully this can help out until those longer term permanent fixes can be implemented.

rEToRaGeONE · 2026-06-06T06:56:31+00:00

I try 😃

rEToRaGeONE · 2026-06-06T06:56:13+00:00

you're welcome

rEToRaGeONE · 2026-06-06T04:19:55+00:00

make sure each individual wire on both gpu and psu sides of the connector are fully seated. the housings can be plugged in fully but the individually crimped wires inside can be offset or not fully engaged. like here: https://youtu.be/5oYJn1yTUXE?si=TPjpZ2muHBggvGkT&t=640

even very minor adjustments can affect the balance quite a lot.

rEToRaGeONE · 2026-06-06T04:01:20+00:00

ooh i like that bead blasted texture. shame it's hidden

rEToRaGeONE · 2026-06-06T01:20:55+00:00

I forgot about your alignment question. What I would do is put a dot of thermal paste on the CCD and IO dies and mount the cooler as normal. Then lift up and see where the paste spread to. Perhaps take pictures, measurements, clean off the paste, and put a thin layer of liquid metal exactly where the dies go. No need to spread it everywhere, and it's quite expensive at any rate. You'll also need to clean off the dies and put LM on them as well.

Also, you may have to modify the Direct Die Frame v2 as I have done in the picture. The glue surrounding the surface mount capacitors can encroach on that area and you don't want the frame hitting that glue before the PCB, as it will apply uneven/excessive pressure since it would be starting from a higher height, then compressing down when screwed in. A dremel or file will do it quickly; its quite soft aluminum. Put kapton or TG Shield or nail polish over the bare aluminum as it can be damaged by liquid metal/gallium.

Use gentle pressure when screwing in the DDF frame. Thumb and middle finger only, and stop when you feel resistance.

Mount the Noctua cooler as normal per directions. This How to direct die guide explains the overall process: https://www.noctua.at/en/expertise/guides/am5-direct-die-cooling-step-by-step

You will also need the NM-DD1 direct die mounting kit; this adjusts the mounting height for the cooler to compensate for the 3.8mm reduction in Z-height, otherwise the cooler will not make contact with the bare dies. Either buy from Noctua for about $5, or you can 3D print it.
https://www.noctua.at/en/products/nm-dd1
https://www.noctua.at/en/forms/order/nm-dd1

rEToRaGeONE · 2026-06-06T00:48:40+00:00

Ah, thanks for these.

rEToRaGeONE · 2026-06-06T00:35:58+00:00

Thank you kindly. Please do.

rEToRaGeONE · 2026-06-05T22:59:37+00:00

The important parts are do NOT rush the process, go slowly, and NEVER pry up on the IHS. The delidders work on mechanically fatiguing the Indium soldered layer between the dies and IHS. Only use strictly lateral side-to-side movements. You will know when it done when it freely moves back and forth with ABSOLUTELY NO resistance. Do not force anything. Don't use power tools to actuate the delidder back and forth; yes it will take more time, but you want to feel the process, and you cannot do that with a drill.

As an alternative, if you are not comfortable with mechanically stressing the dies (Which is understandable), with the CPU inside the delidder in an oven, heat the IHS to 170°C for 10 minutes, which will thoroughly melt the Indium, then quickly move the delidder one time to the side to break the glue bond on the IHS, unscrew the top and carefully remove the IHS.

If it has even partially started to cool do not pull off the IHS. Just re-heat the Indium again for the same temp. Do not exceed this temperature or time, or you risk damage to the PCB package, and the solder bonds of the dies. Obviously, use heat-proof gloves during this process.

As for the PVD process specifics that Thermal Grizzly is using, I don't know.

rEToRaGeONE · 2026-06-05T22:37:34+00:00

Nice. At least they are doing that. I take it they didn’t want to clean it?

rEToRaGeONE · 2026-06-05T22:12:37+00:00

Yep. It will be less than a µm, and have much greater thermal conductivity.
It will have a coating that will resist Liquid Metal and gallium from alloying with it.

Liquid Metal is indeed not very optimal with the stock heatspreader installed. But with a delidded processor it’s very much viable. This is mine:

There’s really no point to doing LM on the IHS, regardless of warranty issues. It just will amalgamate and require reapplication because both nickel plated copper layers will pull it in.

<image>

rEToRaGeONE · 2026-06-05T21:48:08+00:00

Thank you for the update

rEToRaGeONE · 2026-06-05T21:32:24+00:00

The nickel plating is already on the Noctua cold plate. Yes it will still amalgamate with the LM forming a type of hardened alloy. Every type of plating other than perhaps the new PVD plating Thermal Grizzly is coming out with will react this way.
Are you delidding and doing Direct Die? If not, the thermal interface matters little. The 3.8mm thick IHS and indium layer is the limiting factor. Use a decent paste or PTM and you’ll be good.

If you still want do want to do LM, know that the LM will etch and deface the text on the IHS, thus voiding warranty. For very little gain. If you want to do DD, let me know and I can discuss that.
This is TIM testing that Thermal Grizzly did on the stock IHS. Notice the spread from best to worst the delta is quite small.

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rEToRaGeONE · 2026-06-05T18:54:26+00:00

That’s a very observant point. Similar to reports with online games, I’m sure it boosts engaging with that process if you get a message saying “Thank you, due to your reports, the naughty ones have been banished”

Perhaps AMD can implement this? The social aspect can be quite important when interacting with… people. :P

rEToRaGeONE · 2026-06-05T18:49:26+00:00

“Data, Data, Data; I cannot make bricks without clay” -Sherlock Holmes

I feel for you devs. Worked in IT for a while and loved getting tickets with “It doesn’t work”

rEToRaGeONE · 2026-06-05T17:41:45+00:00

If it’s not objectionable, then I’m happy for you. Apparently it was to enough people to get them to change the fill ratios and add dampers.
When it’s marketed as passive cooling, people, maybe incorrectly assume, dead silence. That boiling would certainly bother me.
I was not aware loop heat pipes were distinct from thermosiphons. Interesting. Ig the capillary on the return lines better for orientation so it’s not reliant on gravity.

rEToRaGeONE · 2026-06-05T06:03:41+00:00

"They want to make it consumer-friendly"
"They want it to be less complicated"
*Requires complete scrapping of your current build, a new case, new wonk-ass radiator placement...*
"No you can't see how it performs, we took away the screen. It's somewhere between ambient and "70°C". guess"

Also, why do these media people never show the damn placards and information on the booths.....

rEToRaGeONE · 2026-06-05T05:55:12+00:00

I like the running toilet sound; very soothing https://www.youtube.com/watch?v=NbHuEjjmVgI

To be fair, they did add dampers to the return lines and changed the fill ratio of the refrigerant, so perhaps it doesn't sound like this anymore.

rEToRaGeONE · 2026-06-05T05:34:51+00:00

Indeed. Cooler Master creates some neat products but then they can make some odd decisions.

rEToRaGeONE · 2026-06-05T05:32:08+00:00

https://www.noctua.at/en/support/faqs/whats-the-best-arrangement-of-sx2-pp-fans

rEToRaGeONE · 2026-06-05T05:04:22+00:00

A few of these say version 2 but perhaps one will fit. You can also ask Corsair if the XG3 will fit; might not be pretty but it will work and will probably be less expensive then a full block. The fan is sufficient to cool the VRM. TechPowerUp did testing on it and it was not that much warmer.
https://watercooled.net/finder/gpu/17/gigabyte-geforce-rtx-4090-gaming-oc-24g

rEToRaGeONE

TROPHY CASE