Trouble to upgrade 512 mb ram memory on MB Asus K8N (nforce 3)

[boxy]

I assembled new computer with MB Asus K8N (nforce3 chipset). So far I didnÂ’t have any trouble with these motherboards but use to put only CPU AMD 64. For the first time I put CPU AMD SEMPRON 3000+ (754) and I faced with follow problem. When I install any ram module of 512 mb / 400 ( I used different manufactures Kingstone, PQI, takems Â…) the windows just stuck (it failed to boot up). I have tried to put 2 modules of 256 mb / 400 but it didnÂ’t change anything, the problem was till there. When I install only one module of two above-mentioned the computer is running without any problem. Do I have to change anything in bios since I put Sempron instead of AMD 64. I assembled another computer with Mother Board Asus K8X-X and with all new components equal to this one and I still have a problem with ram memory.

 

[DoomUK]

Run a memory diagnostic like Memtest86+ (do a Google for it, then burn it onto a floppy/CD-RW) to check for bad RAM. If you're having problems with only one DIMM then it's likely a fault with either the other DIMM or a BIOS/Chipset bug.

Is the mainboard's BIOS up to date? In BIOS, is the CPU recognised?

Upon the installation of the new motherboard, did you fomat the HDD correctly?