Stay away from P5GDC Deluxe for gaming -- audio doesn't work (neither does their tech support)

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Frank

I have spent over 5 hours with Asus tech "support" trying to get a
microphone -- any microphone -- to function with a P5GDC Deluxe
motherboard. The answer from tech support is that It won't at any
level that is usable.

The problem is the C-Media chipset on this MB "does not support" a
20dB microphone boost (It took them 5 hours to come up with that
answer). That means that every microphone I am familiar with won't
work (including a $200 Sennheiser 845S).

The board is designed for gaming with a PCI Express 16X AGP, yet they
screwed up the audio.

Asus has always been high on my list ( Ihave bought many of their MB's
and have recommended them to others as well. No more.

I am waiting back for a call from a supervisor. Tier 2 ("Nick") was
worthless.

Anybody else have similar problems.
 
Henk, thanks for posting a reply. It looks like the ASUS "Thought
Police" removed my original post. I guess they don't want
unsuspecting customers to know about the problem before buying.

I wonder if ASUS will send us a free Sound Card as a fix? <g>

Best regards,

Frank
 
Frank S. said:
Henk, thanks for posting a reply. It looks like the ASUS "Thought
Police" removed my original post. I guess they don't want
unsuspecting customers to know about the problem before buying.

I wonder if ASUS will send us a free Sound Card as a fix? <g>

Best regards,

Frank
Click to expand...

The Intel HDAudio spec is here. There is no mic boost in the
spec.

ftp://download.intel.com/standards/hdaudio/pdf/HDAudio_03.pdf

See "7.3.4.10 Amplifier Capabilities" on page 162, for how gain
is specified.

The CMedia datasheet for the 9880 chip is here. Section 5.4.5 on
page 22 lists input amp capabilities, using terminology from the
Intel spec:
http://www.cmedia.com.tw/doc/C-Media CMI9880 Datasheet rev 0.99C.pdf

StepSize = 05h ==> 1.5dB steps
NumSteps = 1Fh ==> 32 steps
Offset = 00h ==> implies no attenuation capability - likely wrong!

Taken at face value, this says the max gain setting is +46.5dB.

If we compare this to a typical AC97 spec, like a Realtek ALC650,
that chip has -34.5dB to +12dB, in 1.5dB steps. And, it has a
microphone boost, for an additional 20dB. That means the Realtek
ALC650 spans -34.5dB to +32dB gain.

So, if we believed the CMI encoding for their gain capabilities,
the gain setting would have more than enough gain for a microphone
(i.e. +46.5dB, as the offset is zero). But, instead, I think the
CMI "Offset" value should be a non-zero value, as it is unlikely
the CMI9880 gain block is all gain - it likely has a range more
like a traditional AC97 chip (i.e. -34.5 to +12dB). To emulate
the mic boost, CMI should have designed the chip to use more
than 32 steps.

It would suggest this is a problem with the CMI implementation
of the Azalia spec, and either the Cmedia control panel is
being confused by the "Offset = 00h" value, or the chip really
only does -34.5dB to +12dB and doesn't have enough gain for anything
other than some kind of amplified microphone (like maybe an
electret mic ?).

It is not likely you would get an answer, but perhaps you could
record your displeasure here. Notice how their web form doesn't
even admit to a CMI9880 chip:

http://www.cmedia.com.tw/etech-re2.asp

Try phrasing your question like "How do I get enough gain to use
my xxx microphone ? Your chip has no mic boost. What is the actual
input sensitivity spec for the chip, for full scale recording ?".

HTH,
Paul
 
Frank said:
I have spent over 5 hours with Asus tech "support" trying to get a
microphone -- any microphone -- to function with a P5GDC Deluxe
motherboard. The answer from tech support is that It won't at any
level that is usable.

The problem is the C-Media chipset on this MB "does not support" a
20dB microphone boost (It took them 5 hours to come up with that
answer). That means that every microphone I am familiar with won't
work (including a $200 Sennheiser 845S).

The board is designed for gaming with a PCI Express 16X AGP, yet they
screwed up the audio.

Asus has always been high on my list ( Ihave bought many of their MB's
and have recommended them to others as well. No more.

I am waiting back for a call from a supervisor. Tier 2 ("Nick") was
worthless.

Anybody else have similar problems.
Click to expand...
No not yet - Ihave other problems tho' during initial set up.

As to the microphone question, if one knows the sensitivity the system
is designed for then presumably one could match a microphone to it.

Since there is a 3 pin hookup, V+ , Signal, Ground, this sounds like
they are looking for a 3 terminal electret microphone.
Most 3 terminal electret's have similar sensitivities and I imagine ASUS
has designed to cover this range.
If you check digikey.com for "Knowles", you will see that all the
"Integral FET Amplifier" mics (AKA Electrets" have sensitivities between
-42 & -32 dB re 1 microPascal.

Bruce Murray

A new P5GDC deLuxe Owner.
 
Thanks for the detailed reply. I see what you mean -- Cmedia's web
site won't even give you this chipset as a choice to ask for help.

For someone not quite as technically well-versed as you are, what is
the best way of identifying this problem on future MB's? Given Asus's
lack of customer support, this will be my last Asus MB for quite a
while.

Thanks again.
 
I have my board set for AC97 audio.

I have three different microphones, and all three of them "work".
The catch is, everything I capture, whether via mics or via line-in
(from a perfectly good sounding cassette tape), whether with Sound
Recorder or the Audacity application, has a terrible ECHO added to the
audio. It sounds like the source is in a giant cave.

Oddly enough, if I turn on the "Monitoring" function and play line-in
audio, the pass-through audio coming out of my PC speakers is perfect;
no echo at all. If I turn on audio capture while still listening in
that situation, the resulting audio capture has the echo added!

I've updated the motherboard BIOS from 1002 to 1006, with no change at
all. I'm using the current CMI audio drivers (CMI9880-51201000736).

I too have to look at adding a cheap soundcard, but I shouldn't have
to!
 
FWIW, I have 2 a7n8x-dlx both with crummy audio from the mic input, 2
different mobos, both have lots of noise in the mic circuit, no fix
available. Basically, I think the mic input circuit for onboard audio
is one of the last design considerations in mobo design.

--
Best regards,
Kyle
| >Frank wrote:
| >> I have spent over 5 hours with Asus tech "support" trying to get
a
| >> microphone -- any microphone -- to function with a P5GDC Deluxe
| >> motherboard. The answer from tech support is that It won't at any
| >> level that is usable.
| >>
| >> The problem is the C-Media chipset on this MB "does not support"
a
| >> 20dB microphone boost (It took them 5 hours to come up with that
| >> answer). That means that every microphone I am familiar with
won't
| >> work (including a $200 Sennheiser 845S).
| >>
| >> The board is designed for gaming with a PCI Express 16X AGP, yet
they
| >> screwed up the audio.
| >>
| >> Asus has always been high on my list ( Ihave bought many of their
MB's
| >> and have recommended them to others as well. No more.
| >>
| >> I am waiting back for a call from a supervisor. Tier 2 ("Nick")
was
| >> worthless.
| >>
| >> Anybody else have similar problems.
| >>
|
|
| I have my board set for AC97 audio.
|
| I have three different microphones, and all three of them "work".
| The catch is, everything I capture, whether via mics or via line-in
| (from a perfectly good sounding cassette tape), whether with Sound
| Recorder or the Audacity application, has a terrible ECHO added to
the
| audio. It sounds like the source is in a giant cave.
|
| Oddly enough, if I turn on the "Monitoring" function and play
line-in
| audio, the pass-through audio coming out of my PC speakers is
perfect;
| no echo at all. If I turn on audio capture while still listening in
| that situation, the resulting audio capture has the echo added!
|
| I've updated the motherboard BIOS from 1002 to 1006, with no change
at
| all. I'm using the current CMI audio drivers (CMI9880-51201000736).
|
| I too have to look at adding a cheap soundcard, but I shouldn't have
| to!
|
| --
| tsnyder at datamirror dot com
|
 
Thanks for the additional info. Perhaps all the sites that review
MB's would do well to include the audio input in their reviews instead
of just the output.

I ended up having to use a USB microphone just to be able to use a
microphone on the Asus board.

My other system is used for voice recognition, so now I will stay away
from Asus and all other MB using the new Intel HD standard if it means
that none of them will work with a conventional microphone.
 
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