Sapphire is one of a few ATI partners to have just released a budget positioned graphics card based on the HD 5550 GPU
Sapphire calls it the HD 5550 Ultimate Silent, and silent it certainly is thanks to the use of a passive cooling system comprising a decent sized aluminum heatsink with a couple heatpipes.
The card comes with 1GB of DDR2 memory onboard. Other specs include 320 Stream Processors, 128-bit memory interface and clock speeds of 550MHz / 800MHz on the GPU and memory respectively.
At the rear I/O is connectivity options for D-Sub, DVI and HDMI. At around $100 U.S. it's not a bad choice if you want DX11 features and silence for your HTPC on the cheap.
Further details in the PR here.