The news here isnt good at all. CPU usage starts out high and goes even higher when we turn on Intel Audio Studios (IAS) DSP effects. On its own, Realteks Sensaura implementation is already riding high at around 13% for DirectSound and close to 20% on DirectSound3D. But adding IAS to the mix pushes those numbers up 10 percentage points on both APIs, with DirectSound at around 23% and DirectSound3D at close to 30%. When you consider that were running on a very beefy 3.4GHz Pentium 4 Extreme Edition CPU, these numbers are that much more disappointing.
3DMark Sound Test
The news here gets considerably better. Running both with IAS enabled and disabled, you can that in both cases turning sound on costs very little in terms of lost frame-rate. With IAS turned off, we see a 2.5% dip (1.6fps) in frame rate, and with IAS turned on, the frame rate drops 4.4% (2.6fps). Both figures are essentially in the noise (so to speak) and indicate that despite the disappointing Audio WinBench numbers, game frame rates shouldnt suffer because of the Realtek HD Audio solution.
IAS overhead however is a bit more noticeable. Even with no sounds running, we saw a 10.4% (6.9fps) drop in frame rate. And with eight sounds there was a 12.2% (7.9fps) drop compared to running with IAS disabled. These frame rates arent terrible, and in a game running in the 60+fps range, would barely be noticed. Where it could make a difference is in a situation where frame rate is already marginal, say around 25-30fps, and the overhead of IAS pulls it down a bit further into noticeable stuttering.
Ad-Hoc Game Tests
We ran the Call of Duty benchmark built into the 1.2 patch of the game, plus the Unreal Tournament 2004 benchmark. UT2004 saw only a minor frame rate hit when turning on hardware 3D audio with EAX. The frame rate dropped from about 67fps with default audio settings to about 65fps with EAX support.
Call of Duty was another matter, however. When using the Miles fast 2D positional audio, we witnessed frame rates of 173 fps. On the other hand, when we turned on EAX1 or EAX2 support, the frame rate dropped to the low 60s. We werent able to run EAX3 -- the game would return to default audio if we tried to run with EAX3 enabled.
Next page: Hands-on time/subjective observations
Dave came to have his insatiable tech jones by way of music—,and because his parents wouldn't let him run away to join the circus. After a brief and ill-fated career in professional wrestling, Dave now covers audio, HDTV, and 3D graphics technologies at ExtremeTech.
Dave came to ExtremeTech as its first hire from Computer Gaming World, where he was Technical Director and Lead (okay, the only) Saxophonist for five years. While there, he and Loyd Case pioneered the area of testing 3D graphics using PC games. This culminated in 3D GameGauge, a suite of OpenGL and Direct3D game demo loops that CGW and other Ziff-Davis publications, such as PC Magazine, still use.
Dave has also helped guide Ziff-Davis benchmark development over the years, particularly on 3D WinBench and Audio WinBench. Before coming to CGW, Dave worked at ZD Labs for three years (now eTesting Labs) as a project leader, testing a wide variety of products, ranging from sound cards to servers and everything in between. He also developed both subjective and objective multimedia test methodologies, focusing on audio and digital video. Before all that he toured with a blues band for two years, notable gigs included opening for Mitch Ryder and appearing at the Detroit Blues Festival.