Pretty much spot-on. At worksize=128, between 180 and 250 the hashrate varies by a couple Mh/s, below 180 it drops fast and above 250 it starts decreasing slowly. By mem clock 300, worksize=256 is ~10 Mh/s faster and peaks at mem clock 354. But the worksize=256 peak @ mem clock 354 is still about 5 Mh/s lower than the worksize=128 peak at mem clock 186.
I wonder why the hashrate is spiking at those values? It seems extremely odd to me that there should be performance spikes at such low clocks. I'd expect them to be at the high end.
If this is not a dedicated rig though, then there is one issue with using mem clocks as low as ~200. Any load on the video card, such as playing video or flash, will lower the hashrate a lot more than at higher mem clocks.
Yeah, I noticed that. I got around the flash problem by disabling hardware acceleration for flash. I also noticed that avi files had no effect on the hash rate but mkv's dropped it to about 50 Mh/s. I'm only downloading xvids from now on, they seem to play ok with AGRESSION set to 6 and I'm trying to avoid or disable anything that uses hardware acceleration.