Sandy Bridge-E and X79 – The ASUS P9X79 PRO Review

Anandtech by Ian Cutress

In the pursuit of sheer performance, a user should aim to combine the ultimate CPU with the ultimate everything else – motherboard, memory, and so on. The latest enthusiast platform to hit our streets is Intel’s Sandy Bridge-E and X79 chipset, released today.

So to start a series of X79 reviews, we are going to have a look at what the X79 chipset brings to the table over other Intel chipsets, and the first motherboard under our microscope is the ASUS P9X79 Pro, coming in at an RRP of $329.99. Needless to say, this is fairly expensive in the land of motherboards, even when pairing it with a $1000 CPU. However, if previous Intel chipsets are anything to go by, ASUS PRO boards get a lot of attention. So the question becomes ‘Is it worth it?’ Read on for the full review.

It seems that every few months or so, we get a new socket and a slew of new chipsets from Intel. If we go back as far as 775 (mainstream), in consumer land, we have covered 1366 (enthusiast), 1156 (mainstream) and 1155 (mainstream). This is in contrast to AMD’s backwards compatibility progression of AM2/AM2+ to AM3/AM3+ (if you ignore Llano and Fusion).

Information has been flying around about the new X79 enthusiast platform for some months now, especially when looking for a replacement for X58. Needless to say, X79 aims at high end and high price. There are the main changes that everyone knows and cares about – quad channel memory and 40 PCIe lanes strike high on anyone’s list about X79. Does that mean the chipset is really for those who want >16 GB of memory, or 2/3 way GPU action?

Above is a block diagram of the routing of the LGA 2011 socket and the X79 Platform Controller Hub (PCH), taken from Intel’s DX79SI motherboard information, which will be reviewed in due course. A few points are specific to that board (dual LAN controllers, USB 3.0 implementation), but it covers the basics of most X79. As we can see, the GPU PCIe lanes are split through multiplexers and switches for x16/x8 or even x4 speeds, depending on the motherboard in question. The connection via DMI from the CPU to the PCH gives the motherboard most of the functionality – PCIe x1, SATA, Legacy IO, TPM, USB 2.0, Audio, Ethernet etc. Most of these features are obviously adjustable by the motherboard manufacturer, in terms of quantity (decrease or increase through controllers), or manipulation, for example ASUS’ SSD Caching, as explained in the ASUS review later.

Firstly, let us look at which niches X79 and LGA 2011 are attempting to cover. read more...