The Promise of HD Graphics - Intel Core i5-661


The Intel H55 Express Chipset

The Intel H55 Express Chipset

The second LGA1156 compatible chipset to be released, the Intel H55 Express chipset, has quite a few features in common with the P55 Express chipset. It's a single-chip solution, with the platform control hub (PCH) communicating with the processor via DMI (and not QPI like the Nehalem Core i7s). The presence of the graphics core on the Clarkdale processor meant that there's a new Flexible Display Interface (FDI) to handle the issue of transmitting the video signals such that they can be output via HDMI, DVI or even DisplayPort. This additional interface for handling video signals is one of the major differences between the H55 and the previously launched P55 chipset.

Both chipsets support dual-channel DDR3 memory (up to 1333MHz) though the PCIe and memory controllers are now both on the processor. Given its mainstream positioning, the H55 chipset is unsurprisingly only capable of supporting a single PCIe 2.0 x16 graphics card, unlike the P55 and its CrossFire/SLI capabilities. The number of PCIe Express x1 lanes have been slightly reduced to six from eight while the number of USB 2.0 ports supported are also cut by two. There's no USB 3.0 or SATA 6Gbit/s support but that's something that we had expected.

The block diagram for the H55 chipset. A new acronym is Intel FDI, which stands for Flexible Display Interface and is used to communicate between the on-die graphics core and the platform control hub (PCH).

The differences between the new Intel chipsets and the only other LGA1156 chipset available, the P55 Express.

The Intel DH55TC Motherboard

From the marketing collateral provided by Intel and the design of the board itself, it's obvious that the company's 'reference' H55 motherboard is predictably targeted at the media-oriented consumer. The micro-ATX form factor coupled with its display outputs meant that it is eminently suited as a media center, with a Clarkdale processor presumably handling the graphics and HD playback. Obviously, one can fit a Lynnfield LGA1156 processor onto this board, though at the cost of not having the integrated graphics functionality.

The board itself is a rather conventional design typical of Intel, though it may initially appear to fall short as a media center for some users due to its lack of optical and coaxial S/PDIF outputs at the rear. There's an onboard header however for those who are willing to do the extra work. Of course, there's the small matter of the Clarkdale platform having support for bitstreaming of Dolby TrueHD and DTS-HD Master Audio via HDMI that should finally make all this audio angst redundant.

We had some minor issues with the layout and placement of certain onboard components, e.g. the single PCIe 2.0 x16 slot was definitely too close to the DIMM slots. As usual, we would also have liked our SATA ports to be aligned facing outwards instead of upwards but these are mostly minor preferences. For the majority of users, it's likely that they will be looking at third party products from the usual motherboard vendors for their H55 fix and not this Intel board. We'll be covering those in a future article.

Intel's H55 motherboard, DH55TC appears to be geared for the home theater PC segment with its micro-ATX dimensions and of course display output options like HDMI.

The rear outputs on this board includes the trinity of display ports, USB ports and Gigabit LAN. There's no optical or coaxial S/PDIF outputs here but there's a header onboard.

The standard 6 SATA ports onboard, with the red ones being eSATA-capable.

Dual-channel DDR3 DIMM slots are expected for this board so it's no surprise to find four slots, supporting speeds up to 1333MHz with a total addressable memory support of 16GB.

A single PCIe 2.0 x16 slot means you can opt for a discrete graphics solution but no multi-GPU of course. The H55 Express chipset is actually under the silver, passive heatsink.

While the H55 chipset can accept any LGA1156 processors, the integrated graphics functionality obviously only works with a 'Clarkdale' processor with the requisite integrated graphics core.