RAM and Motherboard speed problem

I am fine tuning my build but have an issue I can not figure out.

Motherboard - ASUS P5N-E SLI 650i / FSB 1333 MHz
(spec sheet says "memory standard" is 800 MHz)
RAM - Corsair XMS2 800 MHz 4 x 1 GB
Intel Q9300 OC'd 15% to 2.875 GHz

My computer will not boot unless the RAM is set at 667 MHz, it will not boot at any other speed. I have tried every setting in the BIOS that I know how to do (different ratios, linked or not linked, added a little voltage, changed sticks around, tried one stick at a time, even bought new RAM from the QVL list...same thing happens)

No matter what I do nothing will happen if it's not 667 MHz. Is this normal? I would like to run the RAM at 800 MHz....or higher...poeple say this ram can easily run at 1066 MHz. can I even do it? Will I get any kind of performance gain from 667 MHz to 800 MHz or 1066 MHz? I have the latest BIOS and chipset drivers installed. Please send any advice or suggestions! Thanks for the help! :major

XION II case
ASUS P5N-E SLI 650i
Intel Q9300 OC'd to 2.875 GHz
Thermaltake TX2 CPU cooler
Corsair XMS2 800 MHz 4 x 1 GB
Evga 9800 GTX
Antec Neo Power 650w
3 x WD 160 GB
Vista Home Pre 64 bit

 

Is your mobo capable of running at 800 or 1066 with all 4 ram slots populated?

Are these people running 4 ram modules

Have you tried running the cpu at stock and then selecting the higher ram settings (preferably using no more than 2 memory modules for this test)

 

The manual doesn't say anything about RAM speed being limited when you populate all four slots, however, that doesn't mean it can't happen.

It's an SLI board... are you able to get it up to 800MHz if you enable and set the various OC profiles in the BIOS?

 

I have tried every BIOS setting there is....that I know of. All the ratio settings, linked the FSB and RAM, unlinked it and tried different combos. I increased the voltage and nothing works. Two guys in the extremesystems.org forum have the same board and one is running 800 MHz and one even running 1066 MHz with out a problem. They told me to increase my FSB speed....I tried that and the RAM will only still work at 1/2 the FSB speed. Increased the FSB by 20 three times and could only increase the RAM 10....once again only half. I got nervous when I hit 1393 FSB and decided not to go any further. I am a beginner at building...this is my first real build. I am just kinda confused and can't figure out what I am doing wrong. Thanks for any help you can post!:major

 

In the first instance return your cpu to stock speed ie not o/ced

What ram timings are you using? Is your bios set for 1T or 2T Command (in order to problem solve use 2T for now)

 

The FSB speed is not going to be the speed of the memory. The actual speed of the chip is the FSB divided by four (on a dual core CPU anyway), so if FSB is 1333, the chip speed is 333. Take that times the multiplier of the CPU and you'll get your processor frequency. Take it times two and you get the memory frequency, which with an FSB of 1333 will be DDR2-667 (333 x 2 = 666, industry standard is at 667). 667 becomes 1334 if you take it times two, so when looking at the number in the BIOS, your RAM is running at half your FSB speed.

Did any of that make any sense at all?

 

I have never even seen where I could change it form 1T or 2T....I don't even know what that is.

I have my proc at stock speed now....I only OC'd it to run a few benchmarks.

here is a cut and paste of my ram info from PC Wizard 2008

CAS Latency (tCL) : 4 clocks @270 MHz, 5 clocks @400 MHz
RAS to CAS (tRCD) : 4 clocks @270 MHz, 5 clocks @400 MHz
RAS Precharge (tRP) : 4 clocks @270 MHz, 5 clocks @400 MHz
Cycle Time (tRAS) : 13 clocks @270 MHz, 18 clocks @400 MHz
Min TRC : 15 clocks @270 MHz, 22 clocks @400 MHz

 

http://hothardware.com/Articles/Asus_P5NE_SLI_Nvidia_nForce_650i_SLI/?page=4

click on the memory timings thumbnail for Command rate and memory timing settings

Also what values do you have for FSB & Memory (see other thumbnail)

 

Excellent link Risk it summarises what Mimsy was saying and shows the FSB Voltages (i.e. NB Core Voltages).

Okay a simple way to assess if you have enough Voltage going to the RAM please make your CPU FSB clock and multi to "stock". Then increase your RAM; i.e Mem (DDR), MHz to 800 and save and try and reboot, if you have memtest86+ on a floppy or UBCD we can test the RAM. Which is what you really need to do, assess whether your RAM can run at it's SPD settings. Often when you place in 4x1Gb modules this will have a drain on the system and your RAM Voltages (Mem Voltage) and NB Voltages (FSB) need to be increased "slightly", sometimes greater than SPD because of the drain. If you cant get it to boot at SPD settings (800MHz 5-5-5-18) you may need to increase the voltages. Try all above first then I will suggest some Voltages (which you will use at your own risk!).

 

Thanks for the advice! I'll try the memory test tonight. The stock FSB is 1333 for this board and the computer will not boot on the first start up, it will freeze every time. When I hit reset or do a hard restart it will boot fine and everything runs great. Which made me think I needed more voltage...tried that and it would not even boot at all. I am just learning how to build and this is my first real total build...other than this problem everything is great. Ran 3Dmark06 and I am pulling scores around 13,600 right now. Called ASUS for some help...they told me my chip sets are bad and wanted me to return the board. My warenty ended and now they won't take it. Thanks for all the help!:major

 

What exactly is the rated voltage for you RAM? I looked at Corsair's website, but without knowing your part number it was hard to find accurate information.

Under-volting RAM can damage it just as over-volting it can. Not to mention that if the modules are rated at 2.1V they need that much to run at full speed, and sometimes even just to boot. Keep that in mind when you play around with settings. Timings are a lot more flexible, you can use whatever works on your board, but the voltage is important.

 

The default RAM voltage was 1.65 volts on my motherboard. The RAM needs to run at 1.9 volts. I will try setting everything to BIOS default and just adding the proper voltage and test it for a couple days. We'll see what happens :major

 

There's your problem then Good thing you found that out, that will save you major headaches down the road.

But why would it default to 1.65...? Industry standard is 1.8V! :confused