How to overclock X1950XT using ATI Tray Tools?

[t3h l337 n3wb]

I'm trying to overclock my Sapphire X1950XT with ATI Tray Tools (no CCC installed, just the video driver). It says my BIOS core speed is 500mhz and memory is 600mhz (1200 DDR). I'm assuming these are 2D speeds and when I fire up a game, it should go up to the stock 625/1800. However, I've tried it, and it doesn't seem to work. The monitoring graphs still say 500/1200, and performance in Oblivion sucks. I just tried changing voltage from the 1.200V it had before to the stock 1.425V. The core hit 648 with no problems, so that's what I'm at right now. I don't know what stock memory volts are though, so I'm afraid to touch that. How do I deal with these profiles on ATT? I don't understand how I can adjust 2D/3D clocks. I've never owned an ATI card before, and I've always just used Rivatuner to overclock. Can someone walk me through this overclocking process?