Done everything I can think of.
It's annoying knowing that the sound is installed, as I can hear both closing down sounds and opening sounds.
Gigabyte have asked me to chek the memory with memtest. Have already done that. It's new Crucial memory.
They wanted to know what the PSU wattage was. It's 250w but the voltages are good. Besides, there's nothing in there apart from DVD, CPU and HDD.