Um, dunno what you're saying in your edit there.
Your BFG should OC to Ultra Speeds easily, whether you have the reference cooler (plain-jane BFG sticker on reg nVidia cooler) or the "limited" cooler (gold w/heatpipes, 2 fans, and blue LEDs, which doesn't cool as well). If you have the reference cooler, I'd say you could hit 415+/1120+. I think I did like 415(420)/1115 with the "limited" cooler and an AGP slot fan blowing right on the card in a well ventilated case. Now for the OC disclaimer: no card is guaranteed to OC as every other card of the same make/model does. Every single card is different. OCing is a risk no matter what. Yes, OCing voids your warranty in pretty much every case. I've heard of some companies allowing a 5% leeway, but it doesn't matter. OCing is almost entirely untraceable. Usually, the problems that occur when over-overclocking are the same as overheating; thus companies can't call BS on you.
Now for the moral advice: yes, BFG does provide a lifetime warranty. Yes, they are a fvcking awesome company. But I implore you not to take advantage of such a great company by RMA-ing your overclocking card if it blows up. Be a good guy

Besides, this card rocks as it