ASUS sent us the Z87-Deluxe/Quad, a Socket 1150 motherboard for Haswell processors that includes about every type of connector you could wish for. The most exotic one? Thunderbolt 2.0.
Thunderbolt is the interface that combines PCI-Express and DisplayPort in one cable. Thunderbolt is capable of up to 10 Gigabit/s in both directions which makes it perfect for very fast storage solutions. Devices can be passed through or daisy-chained. Thunderbolt has become a standard feature on many Apple products, but it's taking more time to gain a foothold with PCs. There are a few high-end motherboards with a Thunderbolt controller and many of the limited number of Thunderbolt peripheral devices don't have Windows drivers. Nevertheless, the standard is gaining traction in the world of (semi-)professional video editing. And here the arrival of Thunderbolt 2.0 is especially important.
Thunderbolt 2 has two main advantages compared to version 1. The DisplayPort part has been upgraded to DisplayPort 1.2, which includes the Multi-Stream Transport (MST) feature. This is important for 4K monitors because they combine two DisplayPort signals which is only possible with version 1.2. It's not entirely new. The Redwood Ridge Thunderbolt controllers used for current Haswell systems with Thunderbolt also support DisplayPort 1.2.
The most important update is the increase of the maximum transfer rate from 10 Gigabit/s to 20 Gigabit/s. Intel didn't have to change anything physically in the cable. The Thunderbolt 1.0 interface consists of four channels of 10 Gigabit/s each, two for each direction. Each channel is independent, and when both PCI-Express and DisplayPort signals are sent over a Thunderbolt cable, one channel is used for PCI-Express (used for a storage device for example) and the other for DisplayPort. In Thunderbolt 2 both channels can be combined to create 20 Gigabit/s bandwidth in both directions, and data and video can still be sent over one cable at the same time. Intel says this is important for transmitting uncompressed 4K video, which can create streams of 15 Gigabit/s or more. External RAID arrays of multiple SSDs can also profit from the increased bandwidth.
Thunderbolt 2.0 is completely backwards compatible with Thunderbolt 1.0, so any existing Thunderbolt device will work with the new standard. Right now there don't exist any Thunderbolt 2.0 products. And while Intel demonstrated the transfer rate of the 2.0 standard at Computex and IDF we can't test it yet. Something to keep in mind is that current Thunderbolt 1.0 devices can't daisy-chain from Thunderbolt 2.0 devices.
The chip that provides Thunderbolt 2.0 on the ASUS board is the Intel DSL5520, or Falcon Ridge. The board has two Thunderbolt 2.0 ports. Since we can't test it due to the lack of any compatible devices, we'll move on to the other features.