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ATI Mobility Radeon 9600 - Getting acquainted
About 11 months ago we wrote about ATI's then latest graphics chip, the Mobility Radeon 9000. Launched here in London with fanfare usually reserved for desktop parts ATI, who have an impressive history in mobile graphics processors took the clear lead in the mobile graphics stakes with the Mobility Radeon 9000. On March 13 2003 they announced the M9's (as it became known) replacement in the form of Mobility Radeon 9600 or M10 in the hope of building on the success of the M9.

The M10 is quite a large step forward, with many new features being thrown in. Not only does it bring the best performance on notebooks we've seen, we can finally enable 4x full screen anti-aliasing (FSAA) and 8x anisotropic filtering (AF) and get frame rates in excess of 35FPS, which is pretty impressive for a notebook. Aside from the raw performance figures, there are a number of interesting technical advancements too.


Before we delve into the Mobility Radeon 9600, it's important to know the differences in GPUs in notebooks as opposed to desktops. As with any component when placed in a notebook there are certain factors it has to adhere to. Factors such as physical size, heat generation, power management and of course, performance itself.

The last option pales into insignificance if the first three aren't met. In recent years power management has really been the key, with heat generation also causing issues as graphics chips run faster and therefore hotter. Taking a moment to look at power management again, whilst not of utmost importance in "desktop replacement" notebooks; ones that are really designed to sit on desks and only very occasionally be moved, in the "thin 'n light" sector battery life is key.

In essence power management from most manufacturers have a few common traits. Frequency throttling (or underclocking) is commonplace along with disabling parts of the processing unit that isn't required. Whilst these do sound extreme, they make pretty good sense. If you are working on a word processing document or sending email, the 2D work is barely pushing the limits of a high-end mobile graphics chip, so why bother to clock that chip at it's highest possible frequency. A similar experience can be had for the user with the GPU running a little slower, eating up less of the battery juice and of course, producing less heat. ATI coined the term 'POWER-ON-DEMAND' for their mobile GPUs and surprisingly for a marketing term, it does exactly what it says on the tin.

If you think that the notebook sector isn't really of major importance to manufacturers then you are very wrong. The growth in sales of notebooks is, by the most conservative estimate, now equalling that of desktops and many figures show that has now surpassed desktops. The notebook market is going to be one of the biggest battlegrounds for graphics in the coming years.

So with those vectors in mind, lets take a look at the Mobility Radeon 9600 from ATI.

At the time of its launch it was the first GPU made for notebooks that supported DirectX 9.0 and with it Pixel and Vertex Shader 2.0. What does this mean for you? At the moment absolutely nothing because there are no DirectX 9 games available, but like their desktop counterparts, purchasing a DirectX 9 compatible GPU should be seen as more of an investment at the present time and since notebooks generally have a 2-3 year lifecycle, half way through that cycle there will be more than a handful of DirectX 9 games on the market.

Other interesting features include the support of AGP 8x, although very few if not any mobile chipsets currently support this standard (although ATI's recent Radeon 9100 IGP will do so). It may surprise you to hear that the Mobility Radeon 9600 was the first mobile GPU that uses a 0.13micron fabrication process. ATI, keen to throw this in the face of their great rival go as far as to say they managed 'flawless execution' and being 'right on schedule' with the M10.

What really piqued our interest in the heap of features was ATI's OVERDRIVE. The Mobility Radeon 9600 is able to consume around 1 watt in general operation and less than 0.5 watts of power in Windows idle mode. Although that may seem like an arbitrary number, it's very impressive as NVIDIA's high-end mobile chip the NV31M otherwise known as the Geforce FX Go 5600, is able to get around 1 watt of power consumption with their power management tool (named PowerMizer).


With different notebooks having different thermal characteristics OVERDRIVE works slightly differently for each and every notebook, but the general effect is the same.
  • Notebooks must be 'qualified' (ie. been declared stable) at a particular temperature by the OEM. This is done by the OEM.
  • A maximum pre-set frequency is then set depending on the temperature that was qualified by the OEM.
  • Notebooks don't always run at their qualified temperature so when this is the case OVERDRIVE will sequentially raise the speed of the GPU. This is where the thermal sensor that is within the GPU comes into play. When it picks up that the notebook is starting to overheat it will lower the speed of the GPU slightly to cool things down.
  • The difference between OVERDRIVE and POWERPLAY is that the former is aggressive in the way it handles the GPU frequency - it overclocks. POWERPLAY on the other hand underclocks to save battery life. Users can set the thresholds in POWERPLAY to gain extra battery life, but with OVERDRIVE there is no such option because it automatically goes for the most aggressive settings as long as the thermal conditions are suitable.

    Before you get excited by the prospect of huge performance gains through overclocking remember that even though the GPU will run faster than it's standard frequency, we are talking in the realms of 5-15%, however it's great to see companies trying to make use of all available resources in order to gain extra performance.

    With space on notebook motherboards at a premium and high-end GPUs wanting 64 or even 128MB of local RAM the amount of modules that have to be placed on the motherboard cause a conflict with available space. So for the first time ever the Mobility Radeon 9600 has 128MB of RAM built onto the GPU itself. Actually there is an added advantage of having the memory so close to the core of the processing unit. Having an internal bus usually means higher bandwidth and physical closeness decreases latency.

    The Mobility Radeon 9600, through its use of ATI's SMOOTHVISION 2.1 technology is able to support 6x FSAA and 16x AF. Now it would be foolish of us to think that with that enabled we would be getting decent frame rates, however as we find out, with 4x FSAA and 8x AF enabled we were able to get acceptable frame rates. Also present is ATI's FULLSTREAM technology.


    We've explained FULLSTREAM several times over, however simply put it 'de-blocks' video streams with application support coming in the form of Real Networks' RealPlayer.

    Mobile graphics are often described as last year's desktop parts. That may be the case, but the Mobility Radeon 9600 has some very interesting features and represents another step towards bridging the gap between mobile and desktop graphics. So we've seen that the ingredients are present, but have ATI managed to mix them together and cook up a tasty little number?

    Letís find out.
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