DDR 400 only running at 200mhz not 400mhz

[IN4800]

I have the A8N32-SLI Deluxe motherboard from Asus and I can't seem to get my memmory running at its full speed. I have a 2 gig module (2x1GB)from corsair cl3 that should be running at 400mhz but i am only getting 200mhz. I have 4 slots but am only using 2 in a dual channel mode. I need help.. Dose anyone know how to change the setting on the board to run it at full speed.

 

[Gorre]

DDR400 = PC3200 = 200Mhz.

 

[djbbenn]

Where are you reading the 200MHz? Are you sure that's the DDR speed, or just the nominal frequency of the modules?

It shows at 200MHz in some programs and BIOSes because that's the actual frequency, 400MHz is the effective speed due to DDR.

-Dan

 

[IN4800]

Thanks, I veryfied with Asus and they said the same thing. That bios will only show 200, but it is actualy double that.

Is there any program to verify under windows the actual speed. I have cpu-z but it shows around 200 also. Also do you know what is the fastes memmory i can use in the A8n32-sli.

 

[trog100]

cpu-z shows the actual speed its running at.. just double it if u want the ddr factor..

trog

 

[Sasqui]

Thanks, I veryfied with Asus and they said the same thing. That bios will only show 200, but it is actualy double that.

Is there any program to verify under windows the actual speed. I have cpu-z but it shows around 200 also. Also do you know what is the fastes memmory i can use in the A8n32-sli.

No - like ever one said DDR stands for "Dual Data Rate" so DDR400 is really only the memory bus times two 200Mhz x 2 = "DDR"400. It's some truth, some marketing.

If you want faster memory speed - you can overclock your cpu (FSB) and lock the memory to the FSB (1:1). So if you can get your FSB up to say 220 Mhz, your are now running in DDR440 (assuming the memory you have will reach that speed). Also, I don't think there are any boards that support this, but if there was a memory divider that allowed you to run the memory faster than the FSB that would do it. And it's important to note that if you got DDR500 and kept the FSB at 200, you are still running the DDR500 memory at a DDR400 speed.

I have DDR500 in my system and running at 247Mhz FSB with memory at 1:1 - that means the memory is effectively running at DDR 494 (2 x 247).

The ultimate test is to download SiSoft and run memory benchmarks. You should be getting memory bandwitdh of around 4-5 GB/s.

Ultimately - the FSB and divider decides the actual speed your memory is running at.

 

[IN4800]

Thanks, I set it with 12x multiplier and FSB at 230 for CPU at 2760MHZ (64x2 4800+) and my (corsair pc 3200 cs3 3,3,3,8 DDR400) locked at 200mhz for 1:1 giving me 200/200=1 x 230 = 230 x 2 = DDR 460. Do you think thats good enough. I was able to get my CPU up to 10 multiplier X 289 FSB for 2890MHz, I was also able to get my Ram up to locked at 216/200=1.08x235= 253.8mhz x2= DDR 508. I am going to try your settings on my ram and see if they work and cpu at 11x 247. Any suggestions on power settings for the ram and cpu.

Again thanks I appreciate your help.

 

[Sasqui]

Thanks, I set it with 12x multiplier and FSB at 230 for CPU at 2760MHZ (64x2 4800+) and my (corsair pc 3200 cs3 3,3,3,8 DDR400) locked at 200mhz for 1:1 giving me 200/200=1 x 230 = 230 x 2 = DDR 460. Do you think thats good enough. I was able to get my CPU up to 10 multiplier X 289 FSB for 2890MHz, I was also able to get my Ram up to locked at 216/200=1.08x235= 253.8mhz x2= DDR 508. I am going to try your settings on my ram and see if they work and cpu at 11x 247. Any suggestions on power settings for the ram and cpu.

Again thanks I appreciate your help.

Ok, your are getting into more advanced territory. First, if you lock your ram at 200 Mhz, that's all it will run at.

If you want to overclock your ram (which will almost always speed things up), you probably need to first find the highest stable speed it will work at - so I would suggest first picking a low multiplier for the CPU (so it stays within it's working range as you bump up the FSB), then set the RAM to be in sync with your FSB - FSB:RAM should be 1:1. Start bumping up the FSB by something like 5 Mhz increments and run Prime95 for say 1/2 hour each time. Eventually, you will get errors in Prime95, presumably from the memory choking. You can at that point raise the memory voltage to see if that gets you higher. Find the sweet spot. At that point, knowing the highest speed the ram will run at, you can play games with both the CPU Multiplier and the FSB:RAM ratio to get the highest out of your CPU, and keeping the RAM below it's failure point. Be grateful you have a flexible CPU multiplier - it's the best situation to be in.

There are also ways to get the memory to run higher. First is to raise the voltage, but stay within limits! The second is to relax the memory timings, but I don't have the time to write about that Luck.