GA-MA790FX-DQ6 and Corsair 8500C5D problem at 1066mhz

[bustagialla]

Hi, I have bought 2x2048-8500C5D Corsair Dominator (2 ram modules of 2Gb each) and installed them on a Gigabyte GA-MA790FX-DQ6 motherboard with latest firmware (version F7E) and an AMD Phenom X4 945 CPU.
I tried to activate the AUTO XPRESS EPP MODE (with EPP Voltage Control by EPP) but the system crashes tons of times.
The ram modules work perfectly at 800mhz (in auto setting) without any crash.
So, I've tried to set manully the RAM values as indicated below, without success:

Memory Clock x5.33 1066Mhz
DTCs Mode Unganged
DDR2 Voltage Control +0.25 (2.10v)

CAS# latency 5T
RAS to CAS R/W Delay 5T
Row Precharge Time 5T (7)
Minimum RAS Active Time 15T
1T/2T Command Timing 2T
TwTr Command Delay 4T
Trfc0 for DIMM1 127.5ns
Trfc2 for DIMM1 127.5ns
Trfc1 for DIMM1 75ns
Trfc3 for DIMM1 75ns
Write Recovery Time 8T
Precharge Time 3T
Row Cycle Time 31T
RAS to RAS Delay 4T

With these settings I still have many crash. If I get back to the auto settings (800 Mhz) the system works perfectly.
Can anyone help me in tuning the right configuration of the ram modules timings?
These ram modules are listed as certified at 1066mhz on my motherboard, so why they work at 800mhz only?

[bigdaveberg]

I do not mess with settings like that too much but it seems to me that you may be applying too much voltage to the ram. Do not quote me on that, that is only what i think. Maybe DM or someone is searching for you, i am not 100% on my answer but it is a thought.

[Dark Mantis]

Are you overclocking the system as well? The memory voltage does sound a little high to me even though a voltage tweak does usually help. I  didn't notice anything obviously wrong but I expect absic will take a look and this is more his field.

[absic]

Hi,

I would suggest re-setting BIOS to Optimized Defaults and then just setting the Memory Clock to the correct rating for your Memory. Let the system handle all other settings.

Don't forget, as the BIOS version you are running is a Beta version, there could be problems with it and if you can't get your RAM to run properly it might be worth contacting Gigabyte Tech Support as they might have a newer BIOS or an answer for you.

[Dark Mantis]

Having just checked the data in the manual 800 is the maximum clock that can be configured for this board.

Memory Clock
This option is configurable only when Set Memory Clock is set to Manual.
DDR 400 Sets Memory Clock to DDR 400. (Default)
DDR 533 Sets Memory Clock to DDR 533.
DDR 667 Sets Memory Clock to DDR 667.
DDR 800 Sets Memory Clock to DDR 800.

Anything over this and you are into overclocking terrritory and nothing is guarranteed to work, it's just a suck it and see scenario.

[absic]

Actually the manual says: Whether 1066 MHz memory speed is supported depends on the CPU being used.

As the CPU in question is an Phenom ii X4 945 the 1066Mhz should be achievable without overclocking and will be, to some extent, dependant on the BIOS and what settings it allows.

[Dark Mantis]

OK! absic, touche. Damn I knew you would get your own back! Pass the pie.

[bustagialla]

Thanks everybody for your attention to my problem.
I've bought the Corsair Dominator 1066mhz memories because they were indicated as supported (at 1066mhz, even with EPP) on Gigabyte's site.
The 2.1v voltage is indicated by Corsair as the standard voltage for these ram modules, standard is 2.1v with 5-5-5-15 timings, but if I set these timings manually the system crashes, and it crashes even if I activate the EPP (Enhanced Performance Profile) on the BIOS.
I'm quite disappointed about this problem, because I already had 2 Corsair Dominator at 800mhz, and I've bought the new 1066mhz modules to improve the performance, but my pc still run at 800mhz 

[absic]

Have you tried what I suggested earlier?

Re-set BIOS to Optimized Defaults and then just set the Memory Clock to the correct rating for your Memory. Let the system handle all other settings.

I'm quite disappointed about this problem, because I already had 2 Corsair Dominator at 800mhz, and I've bought the new 1066mhz modules to improve the performance, but my pc still run at 800mhz

Have you removed the 800 Mhz RAM modules from your system? If you are trying to run the new modules at the same time they will only run at 800 Mhz.

[Dark Mantis]

I'm quite disappointed about this problem, because I already had 2 Corsair Dominator at 800mhz, and I've bought the new 1066mhz modules to improve the performance, but my pc still run at 800mhz 

To be honest when you are using the computer in a real world scenario you are going to be pushed to notice any speed difference between the two different memories. Much more important is the hard drive speeds(access, read/write etc) These are the things that will slow you down so if you are looking for a performance boost I would say go for a SSD as your boot drive.

[bustagialla]

Have you tried what I suggested earlier?

Re-set BIOS to Optimized Defaults and then just set the Memory Clock to the correct rating for your Memory. Let the system handle all other settings.

Yes, I've done it many times in the past, without success.

I'm quite disappointed about this problem, because I already had 2 Corsair Dominator at 800mhz, and I've bought the new 1066mhz modules to improve the performance, but my pc still run at 800mhz

Have you removed the 800 Mhz RAM modules from your system? If you are trying to run the new modules at the same time they will only run at 800 Mhz.

Yes, I had removed the 2 old ram modules.

[Dark Mantis]

It's a bit of a difficult one, in theory they should run ok even without the EPP set. Just manually putting in the settings should work.
Have you tried running just one module at a time at the stated speed?

[bustagialla]

On Corsair's forum an admin answered me taht maybe I'm running into a limitation of the memory controller on your processor, and to try to raise the CPU/NB voltage.
I'll do some attempt raising these values as soon as possibile and publish the results.

[Dark Mantis]

Upping the NB voltage a little usually helps to make the memory sytem more stable.

[bustagialla]

I have raised the CPU voltage control to +0.050v 10 minutes ago, with all DRAM settings controlled by EPP, and I'm testing the system (which seems stable till now).

Where is the NB voltage? I didn't found it. Is it the same that CPU voltage?
I have noticed into BIOS only the NorthBridge Frequency, not the NorthBridge voltage.
I have just the following items into BIOS regarding the voltage:
CPU Voltage Control (the one I have just changed)
Chipset Voltage Control
HTT Voltage Control
HTR Voltage Control
Memory Controller Voltage

Thanks for your help Dark Mantis.


EDIT: the system has just crashed, so I'm going to increase the Chipset Voltage too, by +.010v. Hope this helps.