Serious problem with my Dual Channel RAMs

[kosmiq]

The problem is in the A64 memory controller (the one built into the CPU-core u know)... Currently it can only handle 4 DIMMs if they run at 166MHz.

Using 2xDIMMs gives the opportunity to run at 200MHz.

Future revisions off the A64 core/memory controller may allow 4xDIMMs @ 200MHz. But as it is now, thats a no go.

So it is not the nForce chip that is the problem, it is the memory controller (and as I said it is built in into the CPU).

I would suggest selling the 4x512mb DDR and buy 2x1024mb instead.

[GLH]

Originally Posted by kosmiq

I would suggest selling the 4x512mb DDR and buy 2x1024mb instead.

That would be a solution. I will think about it.

[DABhand]

2x1GB will still run at 166, as the motherboard cuts the speed to ensure that possible data loss is kept to a very minimum.

[Luciel]

yes cos i ran 2x512 and it still runs at 166

[DABhand]

You can however set the speed manually in the BIOS, but that is not recommended, especially if you use cheap generic memory.

[GLH]

Originally Posted by DABhand

2x1GB will still run at 166, as the motherboard cuts the speed to ensure that possible data loss is kept to a very minimum.

Real

Originally Posted by Luciel

yes cos i ran 2x512 and it still runs at 166

Before i bought the second pair of rams, it was running on 200.

Originally Posted by DABhand

You can however set the speed manually in the BIOS, but that is not recommended, especially if you use cheap generic memory.

The is no option to set the ram speed in my bios.

[kosmiq]

Whenever you install 2xDIMMs it is supposed to run at 200MHz no matter what the size is. As long as the RAM is made for 200MHz, it will run at that speed.

My nForce 2 Ultra 400 will run my 2x1024mb Corsair C2 at 200MHz just as my Asus A8N-Sli Premium.

As I said the memory controller is intergrated into the CPU and that is what is limiting the speed when using 4xDIMMs. Using 2xDIMMs will run at 200MHz if the modules are rated for that.
That's the way it is, I suggest you take a look in the bios on how the memory multipliers are set and if there is any bios that fixes any possible bug between the motherboard and the CPU.