Ok, as I understand it, DDR sends 2 instructions per cycle. Therefore PC3200(DDR400) has an EFFECTIVE clock speed of 400Mhz and an actual clock speed of 200Mhz. This in mind, I have PC3200(DDR400) memory and an MSI NEO Platinum motherboard and in my BIOS it is impossible in any configuration to get my DDR frequency below 333Mhz, infact I have my DDR frequency set right now at 500Mhz with my current configuration, with no problems for about 2 years. So what is the deal? Is my BIOS simply displaying the EFFECTIVE clock speed of the memory or is it actually running at 500Mhz? Also can I get a clarification on what DRAM freq is. From what I have seen depending on what I set it at it seems to have a direct effect on the ratio between my FSB freq. and my DDR freq. Before you flame, know that this is my first and only system I have ever built, so I am definitely no expert.
Either/or is the case usually. I have one motherboard that will go with the actual clock speed, and another than will go with the effective clock speed. You're thinking is correct, but since there's no agreement on the way to proceed between companies, we end up with many people genuinely confused by this matter.
Your dead right about the effective speed and the actual speed. Your ram will using a 250mhz frequency, with two instructions per cycle so it is effectivey 500mhz. When you refer to "DRAM freq" I take it that this is a setting in your BIOS? From what you have said it sounds like its your memory ratio.... ie a ratio applied to your multiplied fsb which determines your memory frequency. Remember your fsb is probably multiplied. ie if you have a 400mhz fsb it is actually a 100mhz fsb multiplied by four. This CPU:MEM ratio will be applied to the 400mhz and not the 100mhz. EDT: BigB must be a quicker typer than me!, beat me by 1min!
