Does that clock give you any artifact? I can run kombustor at 900core with 1100mV but there were obvious artifacts when running 3DMark Vantage, especially the second test. Running the memory at 2250 the first Vantage test the water behaves very strangely...
Also, your screen on Kombustor looks strange... mine looks like this:
Is that screenshot what it looks like to you? does it also look like your screen on stock clocks? or just a screengrab issue?
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