Mystery of ATI Radeon 9600XTs and missing Overdrive feature

AS OUR FUDO reported here (Why PowerColor Radeons are different to ATI Radeons), the prime advantages of ATI-based PowerColor 3D graphics accelerators are that they say they ‘clock' them faster than the ATI reference samples and use faster memory modules to allow higher and/or more stable frequencies.

Yet we recently had the chance to test one of the PowerColor Radeon 9600XT 'Bravo' - model number R96T-C3G - and discovered an interesting anomaly. Unlike the reference ATI Radeon 9600XT cards initially reviewed the world over, the PowerColor 9600XT 'Bravo' had ATI's much touted 'Overdrive' feature disabled.

We tested this with bone-clean installs of ATI Catalyst 3.9, 3.9, 3.10 and the new 4.1s but the 'Overdrive' tab just wouldn't appear.

Here's what the PowerColor Radeon 9600XT 128MB Bravo product page pitches on their Website about ATI 'Overdrive':

ATI products are designed to the highest standards and can now use Overdrive™on the Radeon 9600 XT to explore even higher realms of visual excitement.

Overdrive is the intelligent software solution that determines the optimal ASIC speed for maximum performance. Overdrive™ allows the Radeon 9600 XT to power to every users system."

We took this up with ex-VIA Technologies' Graham Jackson who had recently been appointed as PowerColor's local PR representative.

Graham promptly got to the bottom of it, and reported: "The current version of PowerColor 9600XT cards do not have the LM63 temperature monitoring chip fitted. This means that the Overdrive function cannot be used. PowerColor state that you may cause damage to the graphics processor if you use the Overdrive function (and exceed the max operating temperature) without having the LM63 chip present. They will be fitting this chip to the next release of the card. Therefore, the Overdrive function needs to be disabled in the bios on these first versions of the board. Starting from s/w release 7.97, the display driver will automatically check for the presence of the LM63 device before enabling Overdrive."

Bizarre for a card aimed at the enthusiast community, where overclocking is rife and temperature monitoring can be invaluable.

Graham was keen to stress that the next production run of PowerColor 9600XT will include the LM36 ASIC, so that PowerColor customers can receive the product that's being advertised. We're keen to see what, if anything, PowerColor will do for customers that may have been duped into buying something that is clearly not what is advertised.

Researching further, led us to this discussion at ATI fan-site Rage3d and the problem doesn't seem to be limited to PowerColor alone and is rather more widespread. Owners of ATI Radeon 9600XT based graphics cards by ASUSTeK, Club3D and GeXCube and, surprisingly, Hercules and Sapphire are reporting that their cards are afflicted too.

From this little survey it seems that only ATi Radeon 9600XT cards from Gigabyte and those 'Built by ATI' (BBA), which are only available in North America, are the few 9600XT's that potential customers can guarantee will be fully 'ATi Overdrive' compatible.

We think that ATI should take a keen interest in these shenanigans because, as is the case with the as yet unfulfilled Half-Life 2 bundling promise, a lot of 9600XT boards will have been sold off the back of very positive editorial and that would have been based, in part, on the overall relative value of the bundle and feature set, relative that is to the competing Nvidia's GeForce FX 5700 Ultra.

There's also an entry, written in appallingly bad Engrish, in this FAQ on PowerColor's site:
"Q: Why the overdriver feature have not shown with R9600XT series VGA card ?

There are some different model of the R9600XT VGA card : R96A-C3T series :based on design of Radeon 9600 PRO vga card , not include needed design for overdrive feature. for this model , we have used the memory with higher speed then ATi's recommand , and make the VGA card could running as fast as a R9600XT VGA card with over driver feature . R96T-C3 series :based on new design of Radeon 9600XT VGA card , this model have include needed circuit fo overdrive, if this feature have not show up still, please update VGA driver to newest version".

Some other L'INQs
sapphiretech
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