Confused about OC and artifact detection programs

This is driving me nuts. ATI tray tools says my max core OC is 425/340. But I can run my 9800 Pro 256 at 425/380 without visible artifacts in rthdribl. But, if I set the values to 412/365, I get artifacts right from the start.

I guess I don't understand what ATT is telling me. Just a lousy OCer?

Comments?

Att or ati tool isn't accurate. Don't use it. If you don't see artifacts in games, don't worry about it.When I use them, I get errors from the start. But no problems in games.

I'm also kinda confused. It says scanning for artifacts at teh top of the window. But the higher the OC the longer it would run for. Isn't that backwards. Or is it just that the higher you OC the longer ati tray tool scans to check for artifacts?

I got up to 450 for the gpu and then stopped...

I heard ATI tool was accurate, so that it can detect artifacts as small as one pixel that the human eye can't detect... however that doesn't mean you can't run it higher. I have a 9800 xt and its at 450/390 with a arctic silencer 3 but ATI tool still picks up artifacts on it, I still game with it like this and it works fine for me. As long as the temps are good, then you should be fine running it at a rate where you can't see artifacts yourself.. btw the AS 3 dropped my card temps a good 8 degrees, from 63/74 to 55/65, and helped case/cpu temps too... i really like it http://www.sevenlabs.net/sucka/opio/