Both phones comes with identical specifications. It has 5.5-inch (1280 x 720 pixels) display, while running on the Android 4.4.2 Kitkat OS with HTC Sense 6 UI on the top. Company has already confirmed that these devices will be upgradable to newly launched Android 5.0 Lollipop.
The Desire 820 is powered by an Octa-Core Qualcomm Snapdragon 615 processor, and coupled with Adreno 405 GPU, alongside 2GB of RAM. While the Desire 820q is powered by a 1.2 GHz quad-core processor Snapdragon 410 processor, and coupled with 1GB of RAM. Both devices comes with 16GB of internal storage too.