Asrock Z68 Extreme4
For testing Intel's latest chipset Asrock provided us with their Z68 Extreme4 motherboard, which is currently retailing for $200, making it slightly more affordable than the P67 Extreme6 we tested in our recent P67 motherboard roundup. In fact, we considered the Extreme6 to be the best all-around value for enthusiast shoppers.
Besides the inclusion of Z68's new features, the Extreme4 appears to offer many of the same great features seen on the P67 Extreme6. The spec sheet includes 64Mb AMI UEFI Legal BIOS with GUI support, four USB 3.0 ports, four SATA 6Gb/s connectors, 8-channel audio, eSATA 6Gb/s and Gigabit LAN.
Asrock has added quite a bit of functionality to the stock Z68 chipset. Whereas all Z68 motherboards have six SATA 3Gb/s ports (two can work at 6Gb/s speeds) Asrock has expanded the storage capabilities of their Z68 Extreme4 by including the Marvell 88SE9120 controller, which supports a pair of 6Gb/s SATA ports each using a PCI Express 2.0 x1 (5.0Gb/s) lane.
While the Marvell chip doesn't offer any RAID functionality, it does support NCQ (Native Command Queuing) and it provides the Asrock Z68 Extreme4 with a grand total of SATA ports. Networking is covered by a Broadcom BCM57781 Gigabit Ethernet controller which supports Wake-On-LAN and Energy Efficient Ethernet 802.3az.
Etron EJ168A controllers also occupy one PCI Express 2.0 x1 (5.0Gb/s) lane each to provide a combined four USB 3.0 ports. One controller powers two rear USB 3.0 ports while the other feeds a pair of front mounted ports using the supplied onboard header.
Asrock has added quite a few PCI Express devices and that presents a problem as the Z68 features just eight PCIe 2.0 (5.0Gb/s) lanes. As a workaround, Asrock employs the PLX PEX 8608 switch to deliver eight more flexible ports -- though we suspect many have been used to connect the PLX switch to the Z68. This isn't an ideal solution, but it's the only way Asrock could strap on so much extra hardware.
We found that the 8-channel audio is delivered by a rather traditional choice in the Realtek ALC892 codec which supports THX TruStudio Pro. Despite seeing this chipset on numerous Asrock boards before, we were unable to dig up any real info on it. The Realtek website only lists 8-channel codecs from the ALC861 to the ALC889.