ASUS Xonar DX 7.1 PCI-E Sound Card Review

A Closer look at the Xonar 7.1 DX


The new Xonar 7.1 DX marks the first half-height sound card in the Xonar soundcard lineup since the Xonar D2 and Xonar D2X are both full sized audio cards. The Xonar DX is designed for use in small form factor (SFF) cases and smaller HTPC cases and thus a half height PCI shield is included to help with installing this card into SFF cases. There are various design differences between the DX and other Xonar cards such as the signature EMI shield and blinged-out signal input and speaker output jacks featuring different-colored LED's that correspond to the colors of the jacks. There are also various electronics differences which will be discussed in the corresponding section.


The Xonar 7.1 DX requires more power then what the PCI-E bus can provide and you will need to connect a standard floppy power connector to the card to provide the needed power. The card's driver will remind you to connect the power during installation and the driver will notify you when there is no power to the card in case you forget. The Xonar DX card also features an internal Auxiliary input (AUX_IN) for connecting devices such as television tuners, FM tuners and other add-in PCI cards that require an analog connection to the soundcard. In case you are wondering why there is no CD input on the card, the analog input for CD/DVD devices hasn’t been required for audio transfer since Win 9X days and all audio data is presently transferred through the IDE cable so it is really unnecessary.


Another great addition to this card that many users will appreciate is the front panel audio connector. Many new PC cases will feature front panel audio connectors that allow the user to easily connect headphones and/or a desktop microphone to the front of the case. This is much easier than reaching behind the PC to connect headphones or a microphone. The drivers have settings for enabling the front panel headphone jack which in turn disables the speaker outputs on the card which is very cool feature.

After careful consideration of the input and output options of the Xonar DX and it's possible use as a HTPC card but I see only one glaring issue: The card's digital ouput jack is shared with a line in and mic input. This could conceivably cause trouble for certain types of custom HTPC configurations when digital output is needed along with a line in from a external source. The AUX connector could be routed to a external bracket and get around this oversight.



The Xonar DX 7.1 has from left to right in the PCI Shield picture:

• S/PDIF output, Line_Input, Mic Input
• Front Channel output
• Side channel output
• Centre and Subwoofer channel output
• Rear channel Output

The Xonar DX cards utilize the newer PCI-E 1X slot that are present on newer motherboards as the older PCI specification is gradually being phased out (But not quickly enough for some of us -Ed.). Although graphics cards have grabbed on to the new high bandwidth specification with great enthusiasm, the soundcard industry has been slow to follow suit and have been using PCI for many new designs. Many of us have the PCI-E 1X interfaces on our motherboards but no hardware that uses them. If you’re running low on PCI slots or possibly have none, the Xonar 7.1 DX may be right for you. The PCI-E specification is serial whereas PCI was parallel; the serial transfers of the PCI-E connectors help prevent bus congestion and theoretically help prevent possible audio troubles from such congestion. Sound cards would only use a fraction of the throughput of this slot but the interface isn't widely used yet for other devices making it a perfect interface for sound cards. Eventually PCI will be gone altogether so going with the PCI-E interface makes sense from a upgrading standpoint.