Illustration "12 måneder med Radeon flagsskibe"
As expected the Radeon 9800 XT isn’t a huge leap in terms of performance, and even less so in terms of 3D features. This is no more than a warmed over R350 chip, though it does appear that ATI have actually taken the trouble of a new tape-out and there are, we’ve heard, a few small micro-architectural alterations that may (or may not) become apparent in later driver releases. As architectural cycle times increase due to lengthening of periods between DirectX revisions, increased times between new processes and increasing lengths of time for chips to come back from foundries with each smaller process, it seems like this trend is set to continue - we are likely to see an increasing length of time between each major architectural jump with the frequent smaller performance jumps for each architecture.
Radeon 9800 XT does potentially bring one rather interesting feature in the form of Overdrive, though it's annoying that this isn’t presently enabled by the current driver releases and we weren’t able to get beta drivers that enable it. Although the base clock speed it fairly low, we have heard mutterings of quite outlandish core speed increases, but we’ll reserve further comment until we can test it ourselves. It should also be remembered that although Overdrive could be considered "safe" overclocking, as it won’t clock higher than its pre-specified maximum temperature, the speeds that temperature will be reached at will vary from chip to chip so the maximum clock rates achieved will also vary, much like normal overclocking. We'll take a look at this feature when the Catalyst 3.8 drivers are available in October.
The cooling solution looks quite outlandish and the fan size may put people off, though it is very quiet. The cooling solution is billed as being "silent" and while some may object to the term as anything with a moving part is unlikely to be really silent, there was no noticeable noise over the level of the Pentium 4 CPU fan. The fan speeds are variable according to the temperature of the chip and at the default speeds there still was not any apparent noise from it with high 3D loads; however, it will be interesting to monitor this with Overdrive enabled.
With regards to the performances under the default shipping clock rates, there doesn’t appear to be too many surprises. The testing here has highlighted that while the DDR2 9800 PRO 256MB many have a few latency issues at lower resolution and the 128MB boards are beginning to lose out in more FSAA situations - utilising 256MB of DDR RAM for 9800 XT appears to bring the best of both worlds, with lower latencies but also enough frame buffer space for high resolution FSAA. In general terms, FSAA frame buffer limitations or DDR2 latency oddities aside, the 9800 XT is about 8% faster than the 9800 PRO variants.
In our initial 9800 PRO review we also compared it against the 9700 PRO and concluded then that the performance increase probably wouldn’t warrant an upgrade from 9700 PRO to 9800 PRO. With 9800 XT that goes even more so for 9800 PRO users, especially those with a 256MB board. However we included the 9700 PRO here to see if there would be much worth in going from that to 9800 XT, and we can see that in many cases there is about a 20%-25% performance increase, which whilst isn’t enormous may be a little more attractive for those that are seeking a bit more of a performance hike as newer DirectX9 titles, like Half Life 2, and the 256MB frame buffer also shows some gains with FSAA enabled. However, it should be noted exactly how well 9700 PRO holds up over a year after its release, even with DirectX9 titles such as Tomb Raider.
So, all in all, much as expected the Radeon 9800 XT is another speed bump that pushes ATI’s performance a little higher. Although you wouldn't base a $500 purchasing decision on it, adding the Half Life 2 game to the bundle will sweeten the deal somewhat.
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