Originally Posted by mtcn77
You seem to disregard my comment on Pci-express lanes' power flow. If that 7750 were underpowered, it wouldn't pass the boot check, or else, it wouldn't overclock quite as much as it already does. GDDR5 as well require a lot of amperes next to the gpu, especially as a result of an elevated rate of errors following an overclock.
They have successfully overclocked both the gpu and gddr5; do you recon they overclocked the gpu a bit and then decided to increase memory frequency? I don't think so, they - like every overclocker on this planet does - increased the gpu clocks as high as the card held on and then resorted to memory frequency gains once the gpu consumed all reserve power stored in the capacitors. The card gave everything it had, that's just all there is to it.
Two cards in question 7750 and 7770. Same tech generation, basic difference is 512 vs 640 shaders, core frequency and memory frequency. One card doesn't need to be connected to a PSU,the other does. HC actually said what limited them from going higher was the weak heatsink their 7750 had (they didn't have time to tweak voltage). What I said was that there are more reasons why a 7750 most likely won't hit 7770 clocks.
- In the early days of the process, good CV chips probably became 7770s and the poorer quality ones 7750 due to yields etc.
- There is a reason a 7770 needs to be connected to a PSU and a 7750 doesn't need to, power draw. Even If you have a 7750 SKU that can be clocked as high as a 7770 SKU odds are you won't be able to feed it through the motherboard only, power draw would have been similar to a 7770 (tad lower though) and those need to be connected to a PSU
Both aforementioned reasons are irrelevant to Kaveri igpu. The only common thing between that igpu and Cape Verde 7750 is the amount of shaders, 512 in both cases. AMD isn't pulling 7750 chips to unite them with SR cores, we are talking about totally different dies. Kaveri igpu might or might not be a good overclocker but suspecting it won't be just because 7750 can't get high overclocks is nonsensical.