OK, there seems to be a little disconnect here...
First, what model Antec case are we talking about? With the Antec cases that I am familiar with the front panel speaker and microphone connection often feature an Intel-standard 10-pin connector, with 7 additional individual wires and connectors. If your motherboard supports Intel's standard onboard audio connector (which seems to be the case from review of the DP35 manual), you can plug the 10-pin connector directly into the board. It is keyed so it only will fit one way. Otherwise, you'll need to attach the 7 individual connectors to the motherboard. Here's how:
Locate the internal audio connectors on your motherboard (the figure I spoke of in the previous post). The pin positions are identified on the connectors and on the motherboard diagram; however, the terminology may differ.
1. Connect the AUD GND connector to the ground pin.
2. Connect the FPOUT-R connector to the Front Right Speaker Out Pin.
3. Connect the FPOUT-L connector to the Front Left Speaker Out Pin.
4. Connect the RET-R connector to the Rear Right Speaker Out Pin.
5. Connect the RET-L connector to the Rear Left Speaker Out Pin.
6. Connect the MIC connector to the microphone power pin.
7. Connect the MIC-BIAS connector to the microphone input pin.
Decide on HD or AC97 and set in bios
For Intel® High Definition Front Panel Audio
Pin1 PORT 1L Analog Port 1 - left channel (Microphone)
Pin2 GND Ground
Pin3 PORT 1R Analog Port 1 - right channel (Microphone)
Pin4 PRESENCE# Active low signal that signals BIOS that an Intel® HD Audio dongle is connected to the analog header. PRESENCE# = 0 when an Intel® HD Audio dongle is connected
Pin5 PORT 2R Analog Port 2 - right channel (Headphone)
Pin6 SENSE1_RETURN Jack detection return for front panel (JACK1)
Pin7 SENSE_SEND Jack detection sense line from the Intel® HD Audio CODEC jack detection resistor network
Pin8 KEY Connector key
Pin9 PORT 2L Analog Port 2 - left channel (Headphone)
Pin10 SENSE2_RETURN Jack detection return for front panel (JACK2)
For AC-97 Front Panel Audio
Pin1 MIC Front panel microphone input signal (biased when supporting stereo microphone)
Pin2 AUD_GND Ground used by analog
Pin3 MIC_BIAS Microphone power / additional MIC input for stereo microphone support
Pin4 AUD_GND Ground used by analog audio circuits
Pin5 FP_OUT_R Right channel audio signal to front panel (headphone drive capable)
Pin6 FP_RETURN_R Right channel audio signal return from front panel (when headphones unplugged)
Pin7 AUD_5V Filtered +5 V used by analog audio circuits
Pin8 KEY No pin
Pin9 FP_OUT_L Left channel audio signal to front panel (headphone drive capable)
Pin10 FP_RETURN_L Left channel audio signal return from front panel (when headphones unplugged)
See here