I just bought a 2GB set of DDR400 (2x1GB). They are to fit in my Asus A8N-SLI Deluxe mobo which already had 2x512MB DDR400 in Dual Channel.
I read the mobo manual carefully as to whether or not it was possible to have 2x1GB and 2x512MB running in dual channel together, and it does state that it in fact can as long as they are paired to be equal in each channel.
I chose these sticks since they have the same latency (2.5) as the old ones which the manual stated I should.
I knew that it could very well end up with them not being able to work as intended, so I was/am prepared to ditch the old pair and just settle for the new pair call it a 50/50 chance.
Now& I plugged them in, pairing them so that slots A1 and B1 was with the 1GB sticks, and A2 and B2 with the 512MB sticks. A total of 1.5GB in each channel.
The system recognizes it and it seems fine. However, in the BIOS, the memory clock is now 333 MHz when on Auto setting. With either pair alone, the clock was 400, auto detected.
Anyway, I have set it to Manual and then chose 400MHz. And it runs fine.
I am just wondering how come the system auto set it to 333 instead of 400? And what impact can it have that I have forced it to 400?
And finally, is there any way or tool that allows me to check to ensure that it is in fact pulling from both sets in dual channel?
Long story, sorry about that