I just thought I would share my experience here for the benefit of those who are having trouble OC'ing beyond minimal amounts. In my case I was using an IS7 MB with bios 13, 1 GB of Corsair 3200 XMS C2 latter replaced by 1 GB of Kingston 3500 HyperX, P4 2.4C, Zalman 7000 CU heatsink, Sapphire 9700, 120 GB WD Caviar, and an Antec 1040 case with a 400 watt true power supply. Anyhow, try though I might with both the Corsair and the Kingston memory I was unable to run any setting of GAT. 220 FSB was as far as I could OC with a 1:1 divider and 230 FSB was as far as I could go at 5:4 divider. Using a 3:2 divider made no difference.
Needless to say that after reading some of the success stories here and elsewhere I was dismayed with my results so I decided to RMA my IS7 and try an Asus P4P800 Deluxe. I got the boards swapped out this afternoon and it appears that my IS7 simply had a wall @ FSB 230. Right out of the box with just a couple of OC attempts the Asus board is running steady at 248 FSB 1:1 w/o PAT enabled. I will push it harder and experiement with the PAT settings when I have more time but so far it hasn't failed to post which is very encouraging. Thank you to everyone that shared there experience here it was helpful in deciding what steps to take.
I'll add that I dealt with both Newegg and Googlegear with my equipment purchases and that proved to be fortuitous since I RMA'd the Corsair memory and the Abit board. In both cases restocking fees were waived since I identified defects in the products and the returns came within their guidelines. In retrospect, the Corsair may have worked but that seemed the most likely culprit at the time. Hopefully, this will help other Abit users that are hitting an artificially low FSB wall.