Asus A8V Deluxe: memory underclocking

[TedMarcus]

I recently replaced the Athlon 64 3200+ CPU in my Asus A8V Deluxe with a dual-core 4600+ (I was lucky to find one of these nearly-extinct Socket 939 creatures). I have the latest BIOS (1017), which I allowed to configure its automatic settings (no overclocking or plans to do so). When I got everything set up, I ran CPU-Z. It told me that my RAM was running at 166MHz. It also confirmed that my 2G of Kingston ValueRam PC3200 (4 pieces of KVR400X64C3A/512) was rated for 200MHz (DDR400). So I went into BIOS setup, changed "Memclock Mode" from "Auto" to "Limit," and set the speed to "2:1 (DDR400)".

CPU-Z now shows a memory frequency of 200MHz, and Windows seems happy with it. The other memory parameters that CPU-Z shows haven't changed. I believe that I've merely reset the RAM speed to its correct full rating. But could there be a good reason for the BIOS apparently underclocking the RAM in its automatic configuration?

 

[funkymatt]

4 slots filled=pc2700

 

[GuitarDaddy]

Yep, its because the A8V predates AMD's updated memory controller. A64's prior to Venice cores (Winchester, Newcastle, etc) could only run at pc2700 with all four slots populated.
When the A8V was designed it had to drop the Ramspeed when four sticks where present because the CPU's available required it.

 

[TedMarcus]

Originally posted by: GuitarDaddy
Yep, its because the A8V predates AMD's updated memory controller. A64's prior to Venice cores (Winchester, Newcastle, etc) could only run at pc2700 with all four slots populated.
When the A8V was designed it had to drop the Ramspeed when four sticks where present because the CPU's available required it.

Thanks for the clarification.

So the bottom line with my Manchester X2 is that it's OK to run four slots at PC3200?

I've never seen that limitation documented anywhere. I got the machine with a Winchester 3200, but I never ran CPU-Z until I did the upgrade, so I don't know what it was running at before. But I have what appears to be the final BIOS for the A8V (version 1017, which came out over a year ago). You'd think they would have made the new BIOS set the RAM to PC3200 with CPUs that can support that speed.