why doesn't my DDR3 2000 RAM run even at 14-1500'ish

Andrius

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Post RAM and motherboard model (preferably direct links to specifications).

It is likely your RAM requires a certain voltage at 2000MHz DDR.
You need to set it manualy in BIOS.

If your motherboard supports EPP and the RAM has EPP profiles it could be another issue but the above is the most likely cause.

 

bpogdowz

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ok well here's what i have

I have the super talent ddr3 2000 voltage is listed 1.9
I have the evga 790i up to 2000Mhz with SLI-certified memory

and the XFX model is listed as up to 2000Mhz with EPP 2.0 memory module on newegg.

the SLI DDR3 2000 certified RAM brand is by OCZ

in evga BIOS there is EPP option for the timings so what

voltage is at 1.9 even tried up to 2.0 for kicks

I'm also having trouble even getting the CPU to boot at 3.0Ghz its a Q9450 and i've read all over the place that it easily will click to 3.2Ghz on air.

Yeah I raised chipset voltages and all the voltages to the max green volts in the BIOS and even tried a couple into the red for all voltage parameters and still will not even boot to windows most of the time at 3Ghz.

Oh and it even corrupted my windows install when trying to get a stable boot so I'm guessing what I've read about 7x0i and the overclocking data corruption problem is somewhat true. I'm re-installing the OS right now.
 

Andrius

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1. The Q9450 needs three settings changed in BIOS to get to 3.2GHZ on an Intel based chipset. Those are FSB = 400MHz, FSB:RAM = 1:1(so you don't overclock RAM and that helps isolate potential instabilities) and sometimes Vcore to about 0.05V over VID (usually even Q9300 runs 3.2GHz at stock voltage from my experience but every chip is different so that's irrelevant). With NVIDIA chipsets that's not really the case. It takes a bit of tinkering. Make sure you "unlink" your FSB and RAM to make it easier.
Overclocking on the 790i is a bit of a lottery.

2. What is your RAM voltage at 1333MHz DDR or whatever you run it at right now? Did the board accept the EPP profile? You might need to tell it which profile it should use in BIOS (I'm not really sure how that works anyway).
What profiles are available for your RAM (CPU-Z, Memory and SPD tab)?
Try setting the voltage and timings manualy in BIOS. It usually works for me.

On a side note. Overclocking RAM on the 790i is not really recommended so it might be best if you leave it at "default" values. It doesn't really make that much of a difference perfomancewise anyway.
 

bpogdowz

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Well in short I bought DDR3 2000 to run at the full 2000 and from what you're saying is that no setup currently supports up to the full 2000. I can get it to boot 1:1 ratio but that is only running 667Mhz(333) about 1300Mhz shy of the advertised speed. The guide on TH is vague it says nothing about RAM speed really.

Question: you can't get stability when RAM exceeds that of a 1:1 ratio? BS why do they even sell higher speed RAM then.

To answer your EPP question: the 'profiles' or varibles are disabled, auto, and expert. Both expert and auto will yield the same variants in FSB and unlinked or linked ratios and speeds, however the disabled option only doesn't dynamically adjust RAM timings which is irrelevant to the issue.

P.S. the default value is 2000Mhz because the RAM is DDR3 2000 so no over clocking is done but you say ove rclocking is having a higher RAM speed than the FSB.
 

Andrius

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Well they sell DDR3 2000 because it looks good on paper. If you check this review ( http://www.tomshardware.co.uk/toms-ultimate-ram-speed-tests,review-30648.html ) you'll see that most current boards take no advantage of anything above 1333MHz. Synthethic benchmarks are the obvious exception.

There is no way to get a NVIDIA based chipset stable above it's stock memory frequency (there were data corruption issue notes all over the web). The modules themselves probably work perfectly at the advertised speed.

From what I know (and that's not much) about EPP it should do everything without any help from the user. Things usually don't work that way.
If it doesn't work at 2000MHz run it at 1333MHz and see if it works there.
 

Andrius

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There is no JEDEC standard for DDR3 2000MHz so basicly those RAM sticks are factory overclocked.

These SPD values (from screenshot) indicate that this is infact DDR3 1333MHz. Everything above 1333MHz means you are overclocking them.
To achive DDR3 1333MHz you should run your sticks at FSB:RAM = 333:667 or a ratio of 1:2 at default CPU speed. Or 400:667 3:5 for a 3.2GHz overclock on your Q9450. But that's just my 2 cents.
 

bpogdowz

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I think you cleared things up a bit. I'm new to Intel and just learning the ropes after doing a couple of AMD builds they have corrupted my thinking.
 

Andrius

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Yeah. The FSB:RAM/FSBQuadPumped : DualChannelDDR concepts are a bit freaky comming from an AMD system. I went through the same AMD to Intel transition in late October/early November 2007 being AMD exclusive from December 2000 to October 2007 for my builds.

Anyway NVIDIA should be releasing a patch of somekind tomorrow so maybe it'll make things a bit better (something about video corruption).

Not sure about overclocking stability improvements but running the RAM at 1333MHz should keep you stable and safe until NVIDIA patches up the rest of it's data corruption issues. It's a pity you are not able to run the RAM at it's advertised values but for that you'd need an X38/X48 Chipset.