o/c 4Gb of Corsair 6400C4 on a GA-X38-DQ6?

Paladash

Distinguished
Sep 26, 2007
56
0
18,630
Hi Guys,

After some great help and advice from you guys a few months ago I managed to o/c my Q6600 G0 and have since been reaping the benefits since - e.g. being able to play Crysis on ‘Very High’ settings (Shadows on Medium though) at 1024x768 () at very playable frame-rates.

It’s been a while now and I’m getting itchy feet to have a dabble again; I’m keen to try and o/c the RAM now. I’ve tried a few things but nothing’s stable (Prime95 Small TFT & Blend)..

Given the current BIOS settings below, I just wondered if anyone may be able to offer advice, or point me in the right direction, re suggested settings for o/c’ing my RAM to 1000-1200MHz? (Is this a realistic goal to o/c from 800MHz?).
My RAM = 4 GB (4x1GB) of Corsair ‘2GB DDR2 XMS2-6400C4 TwinX (2x1GB)’
Thanks for your time guys!


Advanced BIOS Features
HDD SMART Capability Disabled
Limit CPUID Max to 3 Disabled
No-execute Memory Protect Enabled
CPU Enhaned Halt (C1E) Disabled
CPU Thermal Monitor 2 (TM2) Enabled
CPU EIST Function Disabled
Virtualisation Technoogy Disabled

Power Management Utility
HPET Mode 64-bit mode

Legacy USB Storage Detect enabled

MIT
Robust Graphics Booster Auto
CPU Clock Ration 9x
CPU Frequency 3.2 (400x8)
CPU Host Clock Control Enabled
PCI Express Frequency 100
CIA 2 Disabled
Performance Enhanced with: Normal
System Memory Multiplier (SPD) Auto
Memory Frequency - 800 800
DRAM Timing Selectable (SPD) 2.00D
** standard timing control **
CAS Latency Time 5
DRAM RAS# to CAS# Delay 5
DRAM RAS# Precharge 5
Precharge delay (tRAS) 18
** advanced timing control **
ACT to ACT Delay (tRRD) 3
Rank Write to READ Delay 3
Write to Precharge Delay 6
Refresh to ACT Delay 42
Read to Precharge Delay 3
Static tRead Value 5
Static tRead Phase Adjust 0
Command Rate (CMD) 2

** Clock Driving & Skew Control **
CPU/PCIEX Clock Driving Control 800mV
CPU Clock Skew Control Normal
(G)MCH Clock Skew Control Normal

System Voltage Control Normal
DDR2 OverVoltage Control +0.3V
PCI-E OverVoltage Control Normal
FSB OverVoltage Control +0.1v
(G)MCH OverVoltage Control (a.k.a. NB voltage) +0.1v
MCH Reference Voltage Cont Normal
DDR Reference Voltage Control Normal
DDR Termination Voltage Control Normal
CPU Voltage Control 1.3
Normal CPU Vcore

 

dagger

Splendid
Mar 23, 2008
5,624
0
25,780
It's realistic to oc from 800 to 1066, 800 to 1200 is not realistic.

Keep NB voltage at default, it offers no real benefits. You might try setting ram overvoltage to +0.4 if the ram is rated at 1.2v, keep at 0.3 if it's 1.1v. Also try loosening timing further and see if it runs stable.

I've been able to go from 800 to 1066 stable at 5/5/5/18 timing at 2.2v, but rolled it back to 800 at 4/3/3/12 at 2.1v. Don't worry too much about ram overclocking. It doesn't make much impact on overall system performance, especially since you have to loosen timing at higher clock, which counters some of the performance gained.
 

Crazy-PC

Distinguished
Mar 29, 2008
204
0
18,680


I agree with dagger, even you keep the RAM voltage at 1.8V it is easy for you to overclock the 800 DDR-2 to 1066while overclock the 800 DDR-2 to 1200 may just success by chance even you set the voltage for RAM at 2.2V.
 

Paladash

Distinguished
Sep 26, 2007
56
0
18,630


(GM)MCH OverVoltage Control .. currently set at '+0.100'
Options on this range from 'Normal' -> +0.025 -> +0.050 -> +0.075 ...etc... all the way to +0.375

MCH Reference Voltage Control
Options on this are 'Normal', '+10%', or '-10%'


PS. I've noticed I've made a mistake on the 'Static tRead Value (AKA MCH Read Delay (tRD)'.. I've listed it as being '5' when, in fact, my BIOS is showing '9'.

As an idea of recent 'attempts' to try to operate at '4-4-4-12', I've tried some Prime95 Blend Tests but no joy:

.. With tRD at 9 and Command Rate (CMD) set at '2T' I get an error after 7mins

.. With tRD at 6 (yes, i should have lowered gradually!whoops!) and Command Rate (CMD) set at '2T' and NB Voltage up'd from 0.1v to 0.125v, the machine had a stuttered reboot and BIOS reset certain values, including CPU clock speed, etc, so it didn't like this

..With tRD back at 9 and Command Rate (CMD) set at '2' (it didn't seem to like 2T, but CPUZ mentioned it as my RAM is EPP) and NB Voltage at 0.125v, I get an error after 57mins so a bit better but not stable I guess...



 

Paladash

Distinguished
Sep 26, 2007
56
0
18,630


Thanks Guys,

I've doubled-checked my RAM (Corsair CM2X1024-6400C4; of which I've got 4x 1GB sticks) and it's rated at 2.1V so, like you say, I best leave the RAM overvoltage at +0.3V (1.8V+0.3V=2.1V).

Like a fair amount of people, I'm seeing if o/c'ing the RAM a bit will eeek out a few more FPS in games but I'm hearing a lot of mixed reviews on whether an o/c from 800 to 1066 will actually make ANY difference, so perhaps I should leave it alone.

On saying this though, I'm running at 800Mhz on very relaxed timings and, with my RAM people are saying I should really try to tighten up these to, say, 4-4-4-12. Trying a few things at the moment (refer my reply to Yellowbeard) but not having much luck so far.

Again, I suppose I could ask... will I see any noticeable difference in gaming on 800MHz Ram at 5-5-5-18 to 4-4-4-12? :)
 

Paladash

Distinguished
Sep 26, 2007
56
0
18,630
PS.. I'm looking at the RAM settings in CPU-Z and, under Memory, it's telling me I'm running at Freq 400Mhz, FSB:DRAM 1:1, 5-5-5-18 and a Command Rate (CR) of 2T. Fair enough.

On the Timings Table, under the SPD Tab, it's showing me the options for my RAM.
JEDEC#1 is for Freq 270Mhz, so I’m ignoring that.
JEDEC#2 shows Freq 400Mhz, 5-5-5-18, and tRC of 22, Command Rate is blank and Voltage is 1.8V.
EPP#1 shows Freq 400Mhz, 4-4-4-12, tRC of 22, Command Rate of 2T and Voltage of 2.1V

As I know my RAM supports EPP and is supposed to run at 4-4-4-12, etc, I’m trying to get it to run as this.

I’ve tried to Google it, but no luck, but what’s ‘tRC’? I’m trying to find out if this a variable I need to change in the BIOS. Somewhere it mentioned tRC=tRAS+tRP but, if this is the case, then tRAS (Precharge delay on my BIOS) would be 12 (if trying to run at 4-4-4-12) and tRP (DRAM RAS# Precharge on my BIOS) would be 4, so tRC=16. CPU-Z says tRC should be 22 if running EPP at 4-4-4-12. I’m a bit confused.. : (