This is the first video showing custom GeForce RTX 3090 graphics card’s PCB with memory mounted on both sides of the PCB.
Custom GeForce RTX 3090 PCB with dual-sided GDDR6X memory
The card used for a breakdown video by a Vietnamese retailer is GIGABYTE RTX 3090 Eagle OC, considered a mid-range custom series in the manufacturer’s lineup.
The design is actually similar to RTX 3080 Eagle OC, which lacks a couple of power stages compared to RTX 3090. In general, both cards appear to use the same board design with Gigabyte’s unique flat 8-pin power connectors with cable extenders. While it does look like a simple solution to a sophisticated problem, this card might not be the best choice for water cooling, as the water blocks require strict reference design, which this card certainly does not have.
For the first time, we can see how a custom board accommodates the additional 14GB of memory, exclusive to RTX 3090 SKU. The Micron GDDR6X technology now only allows 1GB per module (with 2GB modules expected next year). That said, a configuration of 24GBs requires 24 modules. Each module is mirrored on both sites of the PCB. The video shows both sides of the PCB:
The card is a huge triple-fan design (1x 80mm + 2x 90mm) with an I/O bracket occupying two slots, although the card is clearly 2.5 or maybe even 3-slot design (Gigabyte does not list dimensions for this particular model yet).
Source: Hanoicomputer (video taken down) via @I_Leak_VN