According to Geekbench listing LG G5 will be powered by Qulacomm Snapdragon 820 SoC with 4GB of RAM and will be running on Android 6.0 Marshmallow.
LG G5 carries a model number LG F700S, ‘S’ seems to be the specific version for SK Telecom in South Korea. LG has also teased the Always On display for the G5.