This is a detailed measurement of the RealTek HD audio interface in my Dell XPS8930 Desktop system. The XPS 8930 retails for US $1,200 as of this writing so not a low-end desktop tower. Try as I might, I could not find the identity of the RealTek CODEC (ADC/DAC) used in it. Nothing shows up in device manager in Windows, nor can I find anything about it on Dell website.
I am using the Dell to create this review so all I could do for a picture is to use a stock image:
The panther is real though.
There are both front and rear connections. I tested both and performance is the same.
Note that I am focusing on output only. Did not test the microphone.
As an aside, overall I have been happy with the reliability and performance of this Dell machine. Crapware in the form of invasive McAfee anti-virus has been my only issue (it was dumping most of my emails in junk folder).
Motherboard DAC Audio Measurements
I set the system level to 100% and ran my dashboard (using ASIO4ALL):
Ouch. Even at anemic 1 volt output we are clipping badly. As such, it takes the dishonor of showing the worst distortion and noise rating of any DAC tested:
Even without clipping, performance is poor:
If you are going to use this output, best keep the levels below -2 dB. Then again that may cause the downstream amplifier to not be able to reach its full power.
Multitone shows the performance when not clipped:
Sad.
Jitter test shows spurious tones and high noise floor:
Linearity is better than one would predict:
Reason being that linearity test filters out distortion and noise so provides better results.
Dynamic range test shows the high noise floor/low output level:
Headphone Power Measurements
Assuming you may be tempted to use the port just for headphone listening, I ran my usual power tests starting at 300 ohm:
Yuck! We can't even get one milliwatt of power before clipping? In a desktop with plenty of power?
Surely we can do better with 33 ohm load since that is not voltage hungry:
Are you kidding me? Once again it can't go beyond 1 milliwatt? What is going on here?
This is what is going on:
130 ohm output impedance! This internal impedance is eating power even with high impedance loads.
Conclusions
When I was at Microsoft my team was responsible for setting WHQL standards for PC OEMs. In a nutshell, if the PC OEM met those quality standards, they would get a discount on their Windows license. This was our way of enticing the PC OEMs to build better PCs. When I took on the program, the standards were so poor, you could do better with a cassette tape than a PC! So I asked that we raise this level. No sooner than we released the program that I heard cries from Dell/HP like you would not believe. They escalated up to CEO level I think. We stuck to our guns even though what we were asking them to achieve was still way less than what you can expect from 16 bit audio.
We see the results to driving costs down regardless of performance. A headphone amplifier that can't even produce 1 milliwatt of power. Yet Dell wastes money on crapware on effects and such for this interface. Shame on you guys for not spending another 50 cent interface to produce better audio.
Needless to say, you better use an external DAC/amp with these computers. If you don't, I will personally visit you so you do!
Total junk. Not remotely recommended.
------------
As always, questions, comments, recommendations, etc. are welcome.
The sun is out today so forget what I said yesterday about lack of it and depression. I am now in party mood! And what is better for a party than Caviar with hard boiled eggs, diced onions and capers? The garnishes are cheap but now the good Caviar. So please donate to this good cause using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
I am using the Dell to create this review so all I could do for a picture is to use a stock image:
The panther is real though.
There are both front and rear connections. I tested both and performance is the same.
Note that I am focusing on output only. Did not test the microphone.
As an aside, overall I have been happy with the reliability and performance of this Dell machine. Crapware in the form of invasive McAfee anti-virus has been my only issue (it was dumping most of my emails in junk folder).
Motherboard DAC Audio Measurements
I set the system level to 100% and ran my dashboard (using ASIO4ALL):
Ouch. Even at anemic 1 volt output we are clipping badly. As such, it takes the dishonor of showing the worst distortion and noise rating of any DAC tested:
Even without clipping, performance is poor:
If you are going to use this output, best keep the levels below -2 dB. Then again that may cause the downstream amplifier to not be able to reach its full power.
Multitone shows the performance when not clipped:
Sad.
Jitter test shows spurious tones and high noise floor:
Linearity is better than one would predict:
Reason being that linearity test filters out distortion and noise so provides better results.
Dynamic range test shows the high noise floor/low output level:
Headphone Power Measurements
Assuming you may be tempted to use the port just for headphone listening, I ran my usual power tests starting at 300 ohm:
Yuck! We can't even get one milliwatt of power before clipping? In a desktop with plenty of power?
Surely we can do better with 33 ohm load since that is not voltage hungry:
Are you kidding me? Once again it can't go beyond 1 milliwatt? What is going on here?
This is what is going on:
130 ohm output impedance! This internal impedance is eating power even with high impedance loads.
Conclusions
When I was at Microsoft my team was responsible for setting WHQL standards for PC OEMs. In a nutshell, if the PC OEM met those quality standards, they would get a discount on their Windows license. This was our way of enticing the PC OEMs to build better PCs. When I took on the program, the standards were so poor, you could do better with a cassette tape than a PC! So I asked that we raise this level. No sooner than we released the program that I heard cries from Dell/HP like you would not believe. They escalated up to CEO level I think. We stuck to our guns even though what we were asking them to achieve was still way less than what you can expect from 16 bit audio.
We see the results to driving costs down regardless of performance. A headphone amplifier that can't even produce 1 milliwatt of power. Yet Dell wastes money on crapware on effects and such for this interface. Shame on you guys for not spending another 50 cent interface to produce better audio.
Needless to say, you better use an external DAC/amp with these computers. If you don't, I will personally visit you so you do!
Total junk. Not remotely recommended.
------------
As always, questions, comments, recommendations, etc. are welcome.
The sun is out today so forget what I said yesterday about lack of it and depression. I am now in party mood! And what is better for a party than Caviar with hard boiled eggs, diced onions and capers? The garnishes are cheap but now the good Caviar. So please donate to this good cause using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/