Alright, I recently got an HD 7750 overclocked out of the box to 880 mhz on my 300w psu. So far I haven't noticed any problems and it runs great. So I was wondering, how far could I overclock the 7750 without seeing problems due to my low PSU?
If it helps, playing intensive games like Crysis DX10 on very high at 1600x900 and playing Mafia 2 at 1600x900 with anti-aliasing, the card runs doesn't get past 65-75. When playing less intense games at the same resolution, such as Resident Evil 5 at 1600x900 resolution with everything on high rarely get above 60c and usually won't even reach 65c.
There's no huge danger if you don't adjust to voltage. Crank the core and memory clock up in Catalyst Control Center and run graphical benchmarks or games and see if it's stable. I haven't messed with any 7750 but I have OC'd a few 7770s and with two of them I was able to get 30% overclocks with minor voltage bumps and the other one got away with a 15% overclock but it was stable at those clocks on stock voltage. Tinker and have fun, read a guide if you're not sure what you're doing. Tiny voltage increases are okay, just don't get too crazy with it. Try a program like MSI Afterburner it will give you a little more control.
I respectfully disagree. 300watts is more than enough. His GPU draws about 45w on load. Overclocking it with 50 millivolts added on (he wont even need that much) is not going to shoot it up into the 100w range. He can overclock, and probably reach the GPUs clock limits with no damage to and without reaching the power limits of the PSU. I feel this is a non-issue. His card could never draw more than 75w from the motherboard, there are no PCIe 6/8pin connectors, and the card was designed to use much less than what a PCIe slot can provide.
I don't like the fact that he has 300w PSU. And it probably is an OEM that either came with a budget case, or from an OEM computer. His PSU could pose a problem to his system in the future but it will have nothing to do with an overclock on the GPU in question.