I have it stable at 400/800. which is ultra speed on the Core (I'll never hit it on memory though). It kicks. Here's my benches, without tweaking my machine in any way... the benches are being run with antivirus, antispyware, steam, etc. running. Oh, and Rivatuner's HW monitor, to keep an eye on temps.
3DMark01 - 12,000-13,000 (that's that Sempron)
3DMark03 - 9,000+
Aquamark-40,000+
I haven't downloaded 3Dmark05, but I think you get the picture. It's fantastic. I love it. According to Rivatuner, the temps have maxed out at 63, it idles around 47 or less, so that massive heatsink is paying off. It plays HL2 very well at 1280x1024 with everything on high AND 2xAA and 2xAF. It will run at that res with AA and AF juiced, but if I get into a large area it starts to chop, so I tuned them down. It runs about the same at 1600x1200 2xAA2xAF, occasional chops. Runs great at 1600x1200 no AA no AF.
It also runs Halo at 1600x1200 juiced... so I guess the bottom line is, not bad at all for $185.
