Tech Power Up managed to get their hands on a couple photos of the PCBs used in the upcoming AMD Radeon HD 7900 series graphics cards. The blue boards show the traces and connectors that will eventually house the memory chips, graphics processor, capacitors, PCI-E power and video out connections (among others). This particular PCB is allegedly the "cost effective" version that is an alternative for Add-In-Board partners (for example: Sapphire, HIS, and XFX) so that they can offer lower cost cards.
The naked boards feature spots for two DVI, one HDMI, and one Display Port connector, although graphics card manufacturers do not have to include all of the connectors enabling low profile HTPC friendly versions. Further, the PCB features connections for an 8+2 analog VRM (voltage regulators), 12 memory chips, and two 8 pin PCI-E power connectors.
Keep in mind that this PCB is merely a reference design and may not be used in all Tahiti cards. AMD has given its partners free reign to design their own PCBs for the 7950 graphics cards. On the 7970 card; however, the cost effective reference design may well be used in many third party 7970 cards as an alternative to the main 7970 board design.
I suppose we will just have to wait until tomorrow for the official launch to learn more about the new cards. However, being so close to the launch date, the photos are likely representative of the actual PCB design. More photos can be found here.