NVIDIA's nForce 420/220: It's finally here

Integrated Audio Performance

The recent release of the Creative Labs Audigy makes this comparison we're about to do a bit dated however once we are able to test its digital output capabilities we will revisit the audio solution and compare it to the Audigy.  In the interest of time, we have kept this comparison to one of the nForce APU vs. the SB Live!

Other than under UnrealTournament, there aren't many significant performance differences between the nForce APU and the SB Live! in these games.  The performance difference in UT is significant however and it should be noted that it's not present in UT's default 22 kHz mode but emerges as the sampling rate is increased to 44.1 kHz.

These next set of tests were all conducted with a 44.1 kHz sampling rate 16-bits.

Audio Winbench is a very useful benchmark if you know to look at the right sets of numbers.  Here we can see that the SB Live! is clearly not capable of offloading as many tasks from the CPU as the nForce APU.  Normally we'd use a slower speed CPU to show the devastating effects of this but on our 1.2GHz Athlon, 23% CPU utilization just for audio processing is just too high. 

It is worth noting that for most gamers, between 8 and 16 2D voices are common so those are the values you'll want to look at.  Even then, 8.4% is getting quite high compared to what the nForce APU is capable of.  As a reference point, the new Creative Labs Audigy performs much more in line with the nForce APU than with the SB Live!

When dealing with 3D sound streams the CPU usage simply increases.  Here, even with only 8 voices the SB Live! already eats up way too much of the CPU power for audio processing.  With 32 voices, exactly 34% of the 1.2GHz Athlon is devoted to audio processing.  It'd be interesting to see performance under 64 simultaneous voice conditions since the nForce APU can process up to 64 in hardware.  You see, there's a reason that the nForce APU is capable of processing 6 billion instructions per second…