The GTX 650 can be further overclocked and we managed a 4-5 percent performance bump. TGT overclocked the card by 131MHz and we added another 65MHz (1189 to 1249MHz). GTX 650 has no Boost technology so the GPU runs at its maximum clock in 3D.
We overclocked the memory by 300MHz (effectively GDDR5).
The GTX 650 Ultra Charged had an 18 percent faster GPU and equally faster memory, which earned it an 18+ percent performance gain compared to the reference GTX 650.