Need overclocking help!

[sheltem]

Hi, I currently have my setup running at 245x9 = 2205mhz. However my memory is running at 3-3-3-8, but at 2T. When I change it to 1T, winXP won't boot anymore. What other settings should I tweak to get my memory at 1T? And what's the deal with people running their memory async? How would this help me? Any advice would be appreciated as I don't know much about A64 overclocking?