Crucial DDR2 800 (PC2 6400) unstable at stock speed.

[digicube]

ASUS P5W DH Deluxe, Intel Core 2 Duo 6600 2.4 GHz 1066MHz FSB, 4GB DDR2 800 limited to 3.2GB due to Windows Vista Ultimate 32-bit.

I have 4 sticks of Crucial Ballistix 1GB DDR2 800 (PC2 6400) CAS 4-4-4-12. In the mobo BIOS , everything is set to auto and system is stable but I noticed that memory is running at DDR2 667 (PC2 5300) CAS 5-5-5-18. When I change the settings to manual; CPU frequency 266 MHz, DRAM frequency 800 MHz, CAS 4-4-4-12 tWR 6, Memory voltage 2.2V, CPU core voltage 1.35 V. I get BSoD with many kinds of error like BAD POOL HEADER, IRQL NOT LESS OR EQUAL, etc.

Right now everything is set to auto except for CAS, so I'm running at DDR2 667 speed CAS 4-4-4-12, system seems stable.

Do I have bad memory? I'm thinking of getting a different brand to see if system will stably run at DDR2 800. If it doesn't, it's probably a mobo limitation though the manual doesn't specify it.

 

[egale]

Have you tried running at DDR2 800 but with the slower 5-5-5-18 settings?

I had the same memory I think running at 4-4-4-12 DDR2 800 for about 6 months before I started bsoding. I replaced the memory with Corsair 2gb modules that run at 5-5-5-18 DDR2 800 but at 1.9v. My bsods went away after that. I don't notice any real world performance differences either.

I read somewhere that these memory chips are all rated at 5-5-5-18 @ 1.9v. Any modules that claim cas 4 are all at higher voltages which mean they are being overclocked from the get go.

 

[Mr Fox]

Originally posted by: digicube
ASUS P5W DH Deluxe, Intel Core 2 Duo 6600 2.4 GHz 1066MHz FSB, 4GB DDR2 800 limited to 3.2GB due to Windows Vista Ultimate 32-bit.

I have 4 sticks of Crucial Ballistix 1GB DDR2 800 (PC2 6400) CAS 4-4-4-12. In the mobo BIOS , everything is set to auto and system is stable but I noticed that memory is running at DDR2 667 (PC2 5300) CAS 5-5-5-18. When I change the settings to manual; CPU frequency 266 MHz, DRAM frequency 800 MHz, CAS 4-4-4-12 tWR 6, Memory voltage 2.2V, CPU core voltage 1.35 V. I get BSoD with many kinds of error like BAD POOL HEADER, IRQL NOT LESS OR EQUAL, etc.

Right now everything is set to auto except for CAS, so I'm running at DDR2 667 speed CAS 4-4-4-12, system seems stable.

Do I have bad memory? I'm thinking of getting a different brand to see if system will stably run at DDR2 800. If it doesn't, it's probably a mobo limitation though the manual doesn't specify it.

It is Downclocking because of all 4 slots being filled, this is default for 975 x chipset.

Read the MOBO book... !! it really make little difference.

 

[digicube]

egale: Yes I've tried DDR2 800 with 5-5-5-18 and memory voltage at auto. I get BSoD after a few minutes of usage.
Mr Fox: Thanks for the info, There's nothing in the manual that mentions downclocking on DDR2 800 CL 4 but it mentions downclocking on DDR2 667 CL4 and DDR2 533 CL3, I guess they need to revise the manual.
I guess it is a mobo limitation and I don't think getting a different brand will help my situation.

 

[digicube]

Got me G.Skill DDR2 800 with 5-5-5-15 and it has run at 800MHz with no problems for the past 24 hours. No more Crucial for me, G.Skill all the way.

 

[srp49ers]

I just added 2 more stick of crucial ballistix today. running at 4-4-4-12 @2.2v 2T fine.

Should have went to 4gigs a long time ago, what a huge difference it makes in vista.