For our manual overclocking tests, we used MSI Afterburner. Our best results are as below.
The GameRock OC is able to increase the power limit up to 500W when using the card's Performance BIOS. That’s still not as far as the Founders Edition, which can draw up to 600W, but we were still able to add 205MHz to the GPU clock and 1300MHz to the memory.
That resulted in a new average clock speed of 2924MHz, so about 50MHz slower than what we managed with the Founders Edition.
That overclock resulted in gains of 6-7% in the titles we retested. It’s decent, but nothing mind-blowing, though that appears to be the trend for overclocking the RTX 4090 based on the three cards we have tested so far.