The first step after optimizing the memory settings should be to run a few benchmarks to ensure that all of the BIOS options have taken effect. Using the SiSoft SANDRA memory bandwidth tests should show performance increases after even the slightest change to RAS/CAS timings or memory frequency. If the results are the same as with the previous settings, confirm the BIOS options again, and in the case of the i815 and i815E, make sure that your current CPU and motherboard setup does support the selected memory frequency.

After benchmarking, you should then test the new configuration fully to make certain that no stability problems exist. Running several multimedia applications and games should do the trick, but the easiest way to confirm stability is to play extended sessions of Quake 3 Arena. Throughout our various testing on a variety of SDRAM types and speeds, Quake 3 was the one application that quickly illustrated any issues with the BIOS settings. Some PC133 SDRAM will run happily at 2-2-2 and be seemingly stable within Windows, but after crashing out of a few sessions of Quake 3, this game certainly illuminated any chinks in the SDRAM armor.

CPU overclocking may start to cause memory problems when using a non-standard FSB other than 100 or 133 MHz. This is because SDRAM is usually only rated at PC100 or PC133 speeds, so operating at one of the non-standard speeds such as 120 or 140 MHz throws that whole equation out the window. If you own PC133, 3-2-2 SDRAM, it can be an open question as to what memory timings are required when running at 140 MHz. Other than working out formulas using raw timing data, experimenting with the various CAS and RAS speeds is really the only option.

If the CAS and RAS settings or memory frequency speeds need to be lowered to stabilize the system at this overclocked speed, it is quite possible that in trying to gain a few extra MHz, you are actually slowing your system down. While this may only happen when overclocking slightly above the 100 or 133 MHz FSB, while lowering CAS and RAS options from 2 to 3, try to balance the CPU's overclocked speed with the memory's RAS and CAS settings. Use system and game benchmarks to find that perfect mix of CPU speed, CAS/RAS timings and memory frequency.

Another tip for getting troublesome memory to run at a higher speed or rating is to increase the chipset VIO voltage. If the SDRAM boots to the OS, but gives random errors when running applications or games, raising the VIO voltage by .1V may yield greater stability. Keep in mind that any voltage increase entails certain risks and there is always the danger of damaging your motherboard or other components.