Memory Speed Issue! (Asus A8N-E + Opty 144 + OCZ EL Platinum 2GB PC3200)

[jto168]

Hello to all fellow forum members!

I've recently upgraded my system from an old SocketA setup and I'm excited to begin my adventures in overclocking.

I've done some reading regarding the maximum memory speed that you can achieve during overclocking.

After experimenting with a few combinations, I have been able to over clock my system to 2500 MHz at:

278 HTT
9X Multiplier
DRAM Frequency Set @ 266 (aka Memory Divider @ 1:0.66)
3X HT Multiplier

The effective memory speed at this overclock is 179 MHz.

Now my confusion is, the "standard' memory speed of my memory is 200 MHz.
I tried to push the HTT higher to achieve the standard memory speed of 200, but each time I have tried to do so the system would not Post or boot.

Using a memory divider of 266, the memory speed is equal to CPU/14.

Theoretically, I should be able to reach 2700 MHz if I push the HTT to 300 x 9 Multiplier. That would effectively give a memory speed of 200MHz.

I've actually pushed the CPU to 2700 MHz before using generic Samsung PC3200 memory, at 2GB dual channel. I cannot recall what the timings were, but I am sure they are a little more relaxed than the OCZ.

My question is, am I hitting a barrier because of the memory I am using, or the combination of my HTT speed, Multiplier, and Memory Divider settings?
Or could it be that this is a limitation of the CPU itself?

Any help or advice would be appreciated, as it boggles me that I cannot get the memory to run at the specified speed. In fact, at 179 MHz, am I not underclocking the memory?

My system specs is as follows:

Opteron 144
Asus A8N-E (latest bios)
OCZ EL Platinum 2GB Dual Channel PC3200/DDR400 (2-3-2-5, 1T) - OCZ4002048ELDCPE-K
eVGA 7600 GT CO
OCZ PowerStream 520W ADJ SLI PSU
Western Digital IDE 120 GB, and 300GB Drives
2 x LG Optical Drives

Thank you very much for reading my post.

 

[Big Lar]

Well, not all 144's will dance magically Not at stock voltage anyhow, which I am going to assume that is where you are at, as you did not mention anything about it. I would try bumping the cpu volts up just a bit, if the temps are good.

Larry

 

[jto168]

I should've been more specific earlier, sorry about that. More details below.

I realize not all Opterons will overclock like magic, but I'm just wondering why I cannot reach the "standard" memory speed of 200 MHz if I use a memory divider. Is that the sacrifice one makes when trying to push the CPU to its limits and using a memory divider? Does one lose memory speed while attempting to gain CPU speed?

Now before you state that it is the CPU hitting a wall, I have to say that I have reached a stable 2.71 MHz using this same setup, except the RAM consisted of 2 x Samsung PC3200/DDR400 1024 MB. It was running on Prime95 and Stress Prime (same progs I believe, just different GUI) for 8 hours without any problems. At 2.71 GHz, I was able to push the memory speed to 192 MHz or so, as the memory speed would be equal to 2700 / 14 at a memory divider of 266 (1:0.66).

I do understand that CPU speed is KING, but I am just boggled that I cannot reach the standard memory speed of 200 MHz using DDR400 Memory. It's not as if I'm trying to overclock the memory to 295 Mhz

My voltage and other settings for my current setup are as follows:

VCore 1.4125 to 1.5 (adjustments are made in 0.125 increments) * I've not gone over 1.50
DDR Voltage 2.8

At 278 x 9, the CPU speed is 2502 MHz, and the effective memory speed is 178 MHz.
What would be the reason why I cannot reach 192 MHz or 2700 MHz with the OCZ memory? Do I need to relax my memoy timings?

Temps are excellent during overclock. Idle temp is 29C, load is 41C.
Cooling for the CPU comes from an Arctic Cooler Freezer 64 Pro, and my case is an Antec Plus 1080AMG with 5 x 80mm Case fans for optimal airflow.

It's a little loud, but I don't mind it as I always have music playing on the speakers or headphones

 

[jto168]

bump - any help?

 

[TRniTrowood]

I would think that you are hitting a limit due to one of the other buses not the ram, I have A8N-E also with a Opty 148 and it runs solid @2915 with memory@ 333 and due to clocking it runs memory @ little over 200mhz.

 

[jto168]

Originally posted by: TRniTrowood
I would think that you are hitting a limit due to one of the other buses not the ram, I have A8N-E also with a Opty 148 and it runs solid @2915 with memory@ 333 and due to clocking it runs memory @ little over 200mhz.

Could you describe your OC settings?

I'm not sure I understand how I'm hitting a limit due to another bus issue?

 

[bennny]

sounds like you need to loosen some of your ram timings. Is your pci lock on? try like a 2.5-3-2-5, and then start raising them from there, if you cant get it to post any higher.

 

[jto168]

** update **

It seems that this board is very picky with its divider settings, and does not like the 266 divider at higher HTT (fsb) settings using tighter memory timings.

I tried to relax the timings as per the replies, to 3-4-4-8, 2T.
Unfortunately it still did not post at 300 x 9, using a 266 Divider.

But I have finally found the sweet spot for my particular processor.
I was able to achieve a stable 2.6 GHz clock speed, at DDR 470+!

HTT (fsb) = 289
Multiplier = 9x
VCore = 1.4125
DDR VCore = 2.80V
Memory Timings = 2.5-3-2-5, 1T
Memory Divider = 333 (1:0.83)
HT Link Multiplier = 3x
PCI Clock = 100 MHz
PCI Sync Clock = 33.33 MHz
* Effective CPU Speed = 2601 Mhz (2.60 GHz!!!)
* Effective Memory Speed = 236.5 MHz (DDR473!!!)

It's on its 16th hour in (stress)Prime95 right now, and I'm quite happy about the results.

I'm going to run memtest to ensure the memory is working at this speed.