News from videocardz.com states that under embargo marketing materials from Gigabyte confirms compatibility with PCIe 4.0 devices. Although there have been no confirmations about the limitations it might still have some relation to the Rocket Lake-S series.
official marketing materials (which are under embargo) Gigabyte confirms that their motherboards are compatible with PCIe 4.0 devices, however, the functionally is limited. Gigabyte does not directly confirm what the limitation is, however, it is more than likely related to Rocket Lake-S series still being under embargo.
Quote from Gigabyte:
Gigabyte PCIe 4.0 Hardware Design
2x PCIE 4.0 Slot (Reinforced PCIe 4.0 x16 or x8/x8 with lower impedance)
M.2 PCIe 4.0 Slot (M.2 PCIe 4.0 x4 slot with lower impedance)
PCIE 4.0 Turbo B-Clock (External clock generator for PCIe 4.0 overclocking)
PCIE 4.0 Switches (Switch PCIe 4.0 x16 into PCIe x8/x8)
PCIe 4.0 Re-driver (Boost & strengthen PCIe 4.0 signals to longer lengths)
3.3x Slot Signal Stability
4x Lower Low Signal Loss PCB
| GIGABYTE Z490 Motherboards | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Motherboard | Daisy Chain + Shielded Memory Routing | Memory Single DIMM 32GB Support | Extreme Power Design with 90A Power Stage | Direct Power Design | Tantalum Capacitor Array | Nanocarbon Fins-Array | Thermal Guard 2 | Intel 2.5G | |
| Z490 AORUS EXTREME WF | X | X | X | X | X | X | X | ||
| Z490 AORUS EXTREME | X | X | X | X | X | X | X | ||
| Z490 AORUS MASTER | X | X | X | X | X | X | |||
| Z490 AORUS Ultra (G2) | X | X | X | X | X | X | X | ||
| Z490 AORUS PRO AX | X | X | X | ||||||
| Z490 AORUS ELITE AC | X | X | X | ||||||
| Z490 AORUS ELITE | X | X | X | ||||||
| Z490 AORUS ULTRA | X | X | X | X | X | X | |||
| Z490 VISION D | X | X | X | ||||||
| Z490 VISION G | X | X | X | ||||||
| Z490 GAMING X | X | X | |||||||
| Z490 UD AC | X | X | |||||||
| Z490 UD | X | X | |||||||
| Z490 M GAMING X | X | X | |||||||
Here’s a quick preview of some of their motherboards courtesy of Videocardz.com