PC4000 Mix up..

For my system i started out with 512(256x2)MB of PC4000 DDR500 RAM. The sticks are one sided and the company is PQI. I wanst the one who initially bought the RAM so PQI wasnt my choice. But I recently got the money to upgrade my RAM so i bought a stick of 512 PC4000 DDR500 from Corsair. When i try and mix the RAM together though my system wont boot. The RAM timings are the same and i looked at my mobo manual for the RAM configurations. The stick of corsair is double sided and my other sticks are one sided. So it gives me a guide to where i should place the sticks and what speed to set my RAM in my BIOS. After i do all that it doesnt boot. My MOBO is a ASUS K8N-E NF3 with an AMD 3200+ ~2.2ghz. Any suggestions besides buying new RAM? Any help is appreciated.

The PC4000 isn't compatible with that motherboard, it will only take PC3200.

It still works with the MOBO, it just runs at DDR400 speeds. I only boght the 2nd stick at DDR500 speeds becuase i didnt want to mix and match ram types.

That's strange, on the manufacters website it says it will take up to DDR400. So I wouldn't have thought DDR500 would work at all??

mixing and matching ram is never a given.

can you give a bit more info on what settings you're using for the memory? timings/voltage?

in regards to the PC4000, there is no JEDEC spec for DDR past PC3200 speeds, so there is no such thing as "official" PC4000, hence no board shows support for faster than PC3200. All boards should run PC4000 no problem (clocks down to PC3200 or whatever your FSB/memory is set to), just maybe getting them to run at PC4000 speeds is not possible.

Try booting with the single 512mb in. See if you can get that going. If it doesn't work, try clearing the CMOS. Equivilant specs won't mean that different brands will work together as there might be different voltages for each of the companies, as well as the chips themselfs might not like eachother.

The PC4000 stuff will boot up at PC3200 as thats what the BIOS officially supports, and then when the fsb is clocked higher, it'll reach the DDR500 specs.