Intel sent two versions of its high-end Z77 Express-based motherboard, with and without Thunderbolt technology. Unfortunately, we were only giving each vendor one slot each in today's story. After looking at the features its competitors offered, we decided to go with the Thunderbolt-equipped version.
In addition to a single Thunderbolt port, the rear I/O panel offers four USB 3.0, four USB 2.0, and FireWire ports, along with HDMI output and two interfaces to gigabit Ethernet controllers. On the other hand, all three of this board's x1 slots, both of its PCI slots, and its FireWire controller fight for the bandwidth of a single PCIe lane through a single-lane to multi-lane switch.
If overclocking causes the system to stop booting, pressing the Back to BIOS button will force the board to start up with factory settings without losing your custom configuration. The motherboard simply ignores the custom settings until the button is disengaged, allowing users to make minor corrections before trying again.
The reason that so many devices share so little bandwidth is that Intel dedicates most of the Z77 PCH's connectivity to its Thunderbolt controller. And, like Gigabyte, it reserves the CPU's PCI Express lanes for discrete graphics. You don't get a triple-card option. Instead, the x16/x0 lane configuration changes to x8/x8 when an add-in board drops into the second PCIe x16 slot.
Because the bottom PCI Express slot doesn't support a graphics card, we're less bothered by Intel's placement of the USB 3.0 header. On the board's bottom edge, both headers are horribly located. But most PCIe x1 cards are thin enough to prevent spatial conflicts.
Intel moves the DZ77RE-75K's front-panel audio connector up the board’s rear edge by three slot spaces, making it easier for short cables to reach, while simultaneously making finished builds look more cluttered (there’s no way to get the cable to the header without running it over the motherboard’s top).
Two Marvell SATA 6Gb/s controllers add one external and two internal ports to the six controlled by the chipset. All eight of the board’s internal SATA ports face forward to avoid conflicts with long cards, though some older case designs block access to forward-facing ports. Reading chassis reviews help avoid those kinds of problems, though.
A Port 80 diagnostics display and internal power/reset buttons help overclockers bench-test the DZ77RE-75K, but those features are far less valuable once you get the board installed inside an enclosure.
The DZ77RE-75K includes a mouse pad, four SATA cables, a USB 3.0-to-3.5” external bay adapter, an SLI bridge, and a USB 2.0-based Wi-Fi/Bluetooth module. The module is designed to adhere to the back of a solid plastic 5.25” bay cover.