X38 Chipset Overview

Fundamentally the X38 chipset shares all the key technologies already found in the P35 chipset launched in May. The chipset offers support for DDR3 and DDR2 memory types, with DDR3 speeds of up to 1333MHz officially supported. In comparison the P35 chipset is officially limited to 1066MHz, but as any enthusiast will tell you speeds of 1333MHz (and more) are possible with the proper memory modules and motherboard. DDR2 speeds are officially limited to 800MHz, but again most enthusiast motherboards have the proper memory dividers for speeds of 1066MHz and higher.

Like the P35 chipset, X38 supports 1333MHz FSB operation and Intel’s fast memory access technology.

One new feature Intel plans to roll out in X38 early next year is support for their Turbo Memory technology, which launched earlier this year on the mobile side with Intel’s Santa Rosa platform. The technology is designed to speed up tasks like launching a program or application, as well as reducing system boot-up times, but so far results with Turbo Memory have been mixed at best.

Another new feature Intel is rolling out with X38 is Intel’s Extreme Memory Profiles (XMP). Extreme Memory Profiles acts much like NVIDIA’s own SLI-Ready memory. Like SLI memory, Extreme Memory Profile will offer an enhanced performance profile setting in addition to the standard SPD memory settings. Once enabled in BIOS, Extreme Memory will automatically adjust memory timings and voltages to the optimal level of the memory module for enhanced performance over the standard SPD settings. Intel has been working with memory manufacturers and already companies like OCZ have developed compliant modules. The only downside to Extreme Memory Profiles is that it’s currently limited to DDR3.

Another new feature Intel will be launching with X38 is their Extreme Tuning Utility. This software utility acts much like NVIDIA’s nTune software, providing a graphical user interface for controlling system settings like FSB and memory speeds, memory timings, and voltages. These are typically settings an enthusiast would traditionally adjust in the motherboard’s BIOS. With the Extreme Tuning Utility, enthusiasts who would like to dabble in overclocking will be able do this from within Windows.

Intel’s Extreme Tuning Utility is compatible with Extreme Memory and provides manual or automated overclocking functionality, and also offers the ability to save custom profiles; say for instance if you want to have a gaming profile that overclocks the CPU for playing Crysis, and a home theater PC (HTPC) profile that underclocks the CPU for watching movies.

We haven’t personally tried Intel’s Extreme Tuning Utility just yet, so we don’t know how powerful it is or how easy it will be to use. The utility will be bundled by ODMs, who will then be able to tweak the front end to their liking, so someone like Dell may decide to provide an interface with reduced functionality compared to a boutique manufacturer like Alienware. Of course, as many enthusiasts know, motherboard manufacturers like Gigabyte have also produced their own custom programs for years with similar features.

PCI Express 2.0

For gamers, X38’s most prominent new feature is without a doubt its support for PCI Express 2.0. PCI Express 2.0 offers twice the bandwidth of today’s 1.1/1.0 PCI Express, with PCI Express 2.0 graphics cards expected to debut later this year from AMD and NVIDIA. PCI Express 2.0 is backward-compatible with PCI Express 1.1/1.0, so even if you don’t have a PCI Express 2.0 graphics card or motherboard, the devices will still work together, but obviously you won’t get the full 5.0 GigaTransers/second PCIe 2.0 provides.

Intel’s X38 chipset provides two 16-lane PCIe 2.0 graphics slots. This is important for running two Radeon cards in CrossFire mode, which the X38 chipset continues to support despite the AMD buyout of ATI (although obviously Intel doesn’t actively promote CrossFire like they did previously). If you recall, when running two Radeon cards in CrossFire mode the P35 chipset devoted all 16 lanes to the graphics card in the primary PCI Express graphics slot (PEG), the second Radeon card in the secondary PEG slot was bottlenecked to just four PCI Express lanes coming off the South Bridge of the chipset. This solution was far from ideal, and as you can imagine performance suffered as a result.

To test the improvement this brings over P35, we’ve provided Radeon HD 2900 XT CrossFire results with X38 versus P35. Let’s take a look at the numbers!