Palit is one of the first AIBs to release a custom HD 4870 version: the Palit HD 4870 Sonic Dual Edition. It uses a completely revamped cooling system that uses two fans to keep the card cool. Also included is a DisplayPort connector and a "Turbo" switch. The Turbo switch lets you select between two different operating frequencies. In normal mode the card will run at 750 MHz core and 900 MHz memory clock. In Turbo mode an additional overclock is enabled with 775 MHz / 1000 MHz. Even though the changes are numerous Palit has managed to keep the retail price below $299.

Palit has staid with the dual-slot cooling concept of the HD 4870 but completely revamped the cooling solution itself. The card is now cooled by two fans, one 80 mm and one 70 mm. Also the extra space on the slot cover has been used to add a DisplayPort connector and a turbo switch.

The card has two DVI ports and one DisplayPort connector. In case you need an analog VGA port you can use the included DVI adapter. When using an HDMI adapter (also included), you will also have access to HDMI+HDCP+Audio, which allows easy setup of a media PC. All recent ATI Radeon cards have a Realtek HD Audio device integrated inside the GPU silicon. This means that you don't have to connect any additional cabling to the graphics card for HDMI Audio. A new feature of the HD 4xxx Series is support for 7.1 HDMI audio, the older HD 3xxx cards supported only 5.1. While the DisplayPort is certainly a nice addition it is still very new and supported only by a handful of displays.

On the bottom right corner of the slot cover you will find this little Turbo switch. The switch toggles between two BIOSes which are using different frequencies. Normal mode runs the card at 750/950 MHz and Turbo mode runs at 775 / 1000 MHz. Other than that the BIOSes seem to be identical, fan and voltage settings are the same.

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