Mem timings and OC. EDIT (Will aggressive timings during an OC cause a blank screen on startup)?

[MulLa]

Hi

I've been reading posts made by other members in this forum and have noticed that many people have to lower their timings to get a higher OC. Well I do fully understand the concept that lower timings makes the memory more stable at high speed.

But the thing I've noticed is say a person have memory brand X rated at 400Mhz x-x-x-y but once that person OCs their system, with memory speed still under 400 or on 400 but have to lower their timings to something below x-x-x-y. Would that be a motherboard related issue or company X is overrating their memory?


Thanks in advance

EDIT:
Will an over aggressive mem timing ie 2-2-2-5 cause your system to show a blank screen (no beeps no nothing) when upping FSB? Or would this occurance be more CPU related??

 

[canadianpsycho]

Is a stick of RAM is rated DDR400 CAS2-3-3-6 then it should run that speed regardless of whether you are OCing your CPU or not.

The problem arises when you want to go past the declared speed, then you may have to lower the timings. Like trying to run the sample stick at DDR450, you may have to go 2.5-3-3-7

 

[MulLa]

Thanks for the reply.

canadianpsycho what timings did you have on your oc 1.8@2.7? Do you know if you get a blank screen on start up when you oc (no display / beeps whatsoever), would aggressive memory timings cause such an occurance? Or would that be pretty much due to an underperforming chip?

 

[canadianpsycho]

It all depends really.

What are you overclocking and what are your BIOS settings?

Any OC can cause your PC to not POST at all.

I have mym emory at its rated speed (XMS PC3000 @ 2-3-3-6) at default voltage. PC 3000 = approx 394 DDR so my RAM wasn't really out of spec at all.

 

[MulLa]

Well just trying to OC a 2.4 SL6RZ but it just won't go above 2.7 without becoming unstable.

I have Corsair PC3200 the spec says it's a 2-3-3-6-1T chip. It's been running my 1.8A@2.66 so DDR395 at 2-2-2-5 without any problems.

I suspected it was the ram unable to go above DDR395 with 'out of spec' timings. Tonight I did confirm that it was a bad chip that I have. Since I relaxed timings down to 2.5-3-3-6 @ 1:1 ratio but still no go for this particular 2.4. Even tried upping voltage all the way up to 1.65 still no go. Temps were alright at around 55C full load.


So now I'll just stick my 1.8A back in there and hope to sell this 2.4.

 

[canadianpsycho]

Yeah sounds like the CPU is definitely the culprit... Sucks to hear, got a 2.53 I'm looking to try tonight