Equipped with the same high-end Intel network controller, the same ASMedia add-in SATA 6Gb/s controller, the same USB 3.0 hub, and a slightly cheaper audio codec, Asus’ Z87-Plus needs to do something extremely well in order to overcome its price premium compared to ASRock’s competing Z87 Extreme4. Asus has a long list of features that it says add more value than any other vendor, and the USB BIOS Flashback feature is one strong example.
The BIOS Flashback IC resembles an SoC (system on a chip) for its specific function, allowing users to update the firmware with nothing more than a USB flash drive and power supply. Incompatible parts play no role here, since you don't even need to have a processor installed. This is particularly brilliant when a customer purchases an older motherboard that was sitting on a store shelf for months and an unsupported CPU at the same time. Of course, Haswell just came out, so you wouldn't actually need this value-add until later, when Intel refreshes its platform.
Asus skips the I/O panel-based eSATA connector that ASRock shares with an internal port, and instead routes that interface to a connection accessible internally. The Z87-Plus also skips over the Z87 Extreme4's second internal USB 3.0 connector in favor of exposing six ports on the rear I/O panel. Your own preferences should dictate the configuration that works best.
Your needs will also determine the best slot arrangement. Asus splits the CPU’s 16 PCI Express 3.0-capable lanes across two slots, wiring its third slot to slower second-gen pathways from the PCH. While that means the third slot has far less bandwidth, it also won’t steal lanes away from the two graphics cards you might also install. Frankly, Asus' implementation makes more sense for most enthusiasts. But it incurs another drawback: the bottom slot is only wired up to two of those slower PCI Express 2.0 lanes. That means the third physical x16 is almost as ill-suited to a high-end RAID card as it is to three-way CrossFire. Being better for most users is an admission that most folks (particularly in the mainstream space) aren't using intricate storage arrays or three-card graphics setups.
The Z87-Plus doesn't have a POST code display or a bunch of motherboard-based buttons. But it does come equipped with switches. Among them are EPU and TPU mode selectors for automatic under- and overclocking, depending on your power or performance needs. The buttons you do see on-board correspond to power, BIOS Flashback, DirectKey for direct-to-UEFI booting (particularly useful in Windows 8), and MemOK for DRAM-underclocking to assist diagnostics.
We didn’t find any serious layout concerns on the Z87-Plus. Asus moves its front-panel audio connector around an inch forward from its typical location to help builders using cases with slightly short cables, and instead puts a special header for its ThunderboltEX card in the bottom-rear corner.
The Z87-Plus installation kit includes only four SATA cables, though a single SLI bridge and cable-bunching front-panel header extenders are also useful.