it depends...are you using parallel RAID? if so, you should use the application accelerator RAID. if you aren't using iether SATA or PATA, then there's a non-RAID application accelerator you should use.
as for PAT: "Just like the IS7, the IS7-G is yet another motherboard that has successfully mimicked PAT (Performance Acceleration Technology) code previously exclusive to 875P motherboards. As a result the IS7-G is not only slightly faster than every 875P motherboard we've tested but, ironically, also faster than ABIT's own 875P motherboard, the IC7/IC7-G. The procedure for reaping the benefits of PAT-like performance are the same for the IS7-G as they were for the IS7. That is, first make sure your memory timings are as reliably aggressive as your modules are able to withstand. Then, enable the "PSB533" setting under "N/B strap" if you're using an 800MHz FSB processor. After that enable the 1:1 ratio along with the "fixed" option for your AGP/PCI bus. Finally, enable the CPC (Command Per Clock) in the Advanced Chipset Features section. This only applies to users that will be running their IS7-G at stock speeds, if you're overclocking (especially past 250MHz FSB) make sure you use change N/B strap back to PSB800 so as to not max out your memory too quickly. A 3:2 DRAM:CPU memory ratio is usually your best bet past 250MHz FSB if you don't have expensive memory rated higher than PC3200 (DDR400). Otherwise 5:4 is still possible with high-speed memory validated at DDR433 (PC3500) or DDR466 (PC3700)." - 865PE/875P Motherboard Roundup June 2003 - Part 1: 20-way Shootout @ AnandTech