AMD Ryzen 7950X 'Zen 4' CPU delidded: gold-plated CCDs, looks gorgeous

AMD's new flagship Ryzen 9 7950X "Zen 4" processor has been delidded, where we get a peek behind the scenes of AMD's very latest CPU.

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The delidding was performed by GamersNexus, which ripped the chip apart to spy on the two CCD configuration that is only used on the flagship Ryzen 9 7950X and Ryzen 9 7900X processors. There are three dies in total: two Zen 4 CCDs that are made on the TSMC 5nm process node, while the I/O die (where the RDNA 2 GPU also resides) is made on the TSMC 6nm process node.

AMD's new Ryzen 7000 CCD measures in at 70mm2 compared the bigger 83mm2 for Zen 3, transistor-wise that's a 58% increase in transistors: Zen 4 has 6.57 billion transistors on TSMC's new 5nm process node, while Zen 3 has 4.15 billion transistors on TSMC's current 7nm process node.

Normally we have multiple SMDs (capacitors, resistors) that are regularly placed underneath the package substrate, with AMD shifting them to the top layer of the CPU which requires a new design of IHS (integrated heat spreader) that is internally called "Octopus". The reason for the Octopus naming is because it's an Octopus-style IHS with 8 arms that even Robert Hallock, the Director of Technical Marketing for AMD, calls the "Octopus".

Each of the 8 arms are placed next to the huge array of capacitors, with the arms also raised just slightly so that there's room for the SMDs. Overclocker 'Der8auer' explained to GamersNexus that when it came to the gold-plated CCDs that there's an aspect that you can solder indium to gold without the need of flux. This makes the process easier, where he notes that you don't need aggressive chemicals being placed on your CPU.

However, without the gold coating Der8auer explains that it would also theoretically work to solder the silicon to copper, noting that it would be "more difficult and you would need the flux to break the oxide layers".

The gold-plated IHS is not just beautiful but it's useful: boosting the thermal dissipation from the CPU and I/O dies of the Zen 4 processor, directly into the IHS. AMD is using liquid-metal TIM (Thermal Interface Material) on both the two 5nm Zen 4 CCDs and 6nm I/O die, which helps heat conductivity, while the gold plating helps with heat dissipation.

Der8auer explained to GamersNexus: "Regarding the gold coating, there's the aspect that you can solder indium to gold without the need of flux. This makes the process easier and you don't need aggressive chemicals on your CPU. Without the gold coating, it would theoretically also work to solder the silicon to copper, but it would be more difficult and you would need the flux to break the oxide layers".