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As you may know, integrated graphics aren't focused on insane fill rates, huge memory throughputs or generally pitching as much silicon at the 3D pipeline as possible.

They're more about offering a reasonable feature-set in a limited amount of space for the everyman. As a subset of this market, mobile integrated graphics are even more focused, having to take into account thermal design power (TDP) on top of the other design constraints, while accepting that there probably isn't a discrete upgrade path available.

Unquestionably due to its position in the marketplace, rather than the capabilities on offer, Intel's Graphics Media Accelerators (GMA) can be found in more laptops than any other manufacturers' chipsets.

The latest revamp to the Centrino chipset, previously codenamed Santa Rosa, also ushers in a new graphics engine, but should end users, and ultimately laptop builders, be looking elsewhere for their graphics engines? Or is there just enough on offer here to keep its intended market placated?

Before we discuss the merits and deficiencies of Intel's latest, it's worth putting the capabilities of this chipset into the context of who they're designed for, and that's essentially the casual gamer. If you're looking to play modern titles such as Bioshock or Unreal Tournament 2007, then you really need to invest in a proper discrete graphics solution. Integrated graphics are aimed more at the likes of World of Warcraft or older, last-generation games such as Doom 3.

The biggest news about Intel's new GMA X3100 is that it supports hardware Transform and Lighting (T&L) and programmable shader units (up to 128).

The engine runs on a 500MHz clock, boasts Intel Clear Video Technology (which improves quality), supports Vista's Aero prettiness and can potentially output to an HDMI connector as well. API support comes in the form of DirectX 9 and OpenGL 1.5. This, combined with improved power-saving states, make this one of the most significant updates in recent times.

The GMA X3100 also continues the philosophy of Intel's previous graphics solutions (going back as far as its discrete i740 line), and that is one of compatibility. While there's rarely been the power available to run games at anything more than PowerPoint slideshow speeds, being able to render those images correctly means that you'll often put up with poor frame rates as long as everything looks right.

In testing, the improvement this new engine offers over the older solutions isn't massive - 3DMark06, the industry benchmark for ascertaining the capabilities of graphics engines in general, returned a score of 416. While this result is twice that from the previous generation of integrated graphics, it still proves that integrated graphics aren't for next-generation titles. Top-end cards score around 8,000, with even cheaper cards managing scores around the 4,000 mark.

In real-world performance terms, the low throughput of this engine shows when trying to play Doom 3 back at the high-quality setting at 800 x 600 - less than 10fps isn't playable. Half-Life 2 fared a little better at 18fps, but surprisingly this score is bettered by its last-generation graphics, which were 5fps smoother. Despite the presence of hardware T&L, the lack of fill rate is clearly a limiting factor.

Newer drivers should improve the performance on offer - somewhat surprisingly, even Windows Vista currently only rates the capabilities of GMA X3100 as a 3.0 in its Gaming Index.

The fact that it offers programmable shader units means that the drivers can be tweaked to get the best performance out of individual titles, although whether Intel is prepared to invest so much time and money in something that isn't aimed at gamers is questionable.

The improvements to the video rendering engine are more immediate - video playback is less processor intensive and actually does look better. Playing back HD content stressed the CPU by only 15 per cent using WMV content, and even the usually punishing H.264 trailer suite we use for testing averaged out at an impressive 40 per cent.

Colours were more vibrant and the results weren't so obviously affected by jaggies. The improved quality and performance of the video playback engine makes this a more tempting option for watching HD content though, especially as the chipset supports HDMI (complete with HDCP).

Of course, now that AMD has swallowed up ATi, there's the potential for a real battle in the integrated graphics sector. Hardware T&L means this chipset is already a couple of inches ahead of ATi's R690, which can't be good news for the newly combined company.