Yeah Wolly, your card will run near 2000mhz when playing by itselft! with your overclock it could run at 2125 (aprox.) when overclocked.
Did you achieved +150 OC stable on Unigine Heaven? Did you try MSI Kombustor -> GPU core burner (Furry MSI)? That's a great tool to confirm the OC once it's stable, firstly, on Unigine (and it's not as agressive as Furmark, without infecting the TDP).