If your using Nvadia reference drivers the "coolbit" trick works great. I don't remember where the heck I got it but if you want I can send it to you. On my Guillemot Prophet I noticed quite the increase from o/cing
Technically, no. You are overclocking the AGP bus, but not any of the components of the card.
Usually, people who are overclocking their video card are raising the core and memory speeds. Since yours are still running at the presets, you're not overclocking the card.
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From another BBS:
"hmm... Cyrix III, huh? You can put syrup on sh*t, but that don't make it pancakes."