Win 7 64bit and 8 GB of ram

Defiant306

Defiant306

Defiant306

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Just had one strange experience

I got another 4 GB of ram recently, popped it in. Same Corsair C5D Dominator ram at 1066Mhz. The board supports this ram and speed.

Anyway I booted Win 7 and got a BSOD on the boot screen, rebooted it again got into windows, lots of memory reference errors then 20 seconds later BSOD.

Tried running the new memory instead of the old in the primary slots and the system is stable as well with just these 2x 2GB sticks.

Anyone experienced this issue with windows before? Any fixes or does a reinstall fix this?


Any advice greatfully recieved!
 
Defiant306 said:
Why would that be can I ask, surely the board should provide the correct voltage, no?
Click to expand...

Not always, the board will try the voltage from the SPD information provided by the memory modules, which as a rule works fine for pairs of memory, but by the time you add another pair it can be a bit low.

I seem to remember that when I built my current PC, I had to up the voltage to the memory (4x2GB) to get it to pass memtest without problems, mind you I only had to up it by the smallest increment possible (+0.25v) so it's not like I was frying the modules.
 
You're trying to run 4 sticks of RAM on an overclocked board, that puts more strain on the memory controller than just 2 sticks - hence why it's stable with just the new RAM.

You'll either need to fiddle with the vDIMM as marc suggests or possibly even wind back the overclock.
 
You will probably find with the overclock that you need to change the memory divider. I was running my RAM at 1000mhz when 4gb, but upon upgrading to 8gb I had to change it to 800mhz.

It's the overclock in my case, you may or may not get away with a little more voltage.
 
Did you specifically check if your motherboard supporting that type of ram with all slots populated?
Often they will support one bank filled or the other, but need very specific memory to populate all slots.
Increased voltage is often a way around this.
 
Yes but the same list down below has the QVL list of verified and working dimms, it is an ASUS motherboard, they only support certain ram subtypes, those they have tested.

Its never usually a problem with filling 2 bansk, but becomes a problem when you wish to populate all 4.
Is your RAM on the list?
Try upping your voltage.
 
It's nothing to do with the OS - purely a hardware problem.

Just changing the memory voltage may not fix it. You might well need to bump up the chipset/northbridge voltage as well, especially if the system is overclocked. You will probably find that your max overclock is lower with 4 sticks than with 2, whichever settings you try. It just puts more load on the memory controller.
 
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I think tonight I will try running all 4 dimms at 800Mhz and see if windows is stable at that.

If all is ok after that I will try uping the voltage on the memory first and then the North/south bridges if I get no better results.

To be honest I've not really considered this as an overclock considering the memory does this natively and the Asus manual just states that I need to change the frequency in the bios to take advantage of 1066Mhz.

Thanks all for the advice so far, I will report back with the results. :)
 
It's simple. More work the controller has to do the more power it needs i.e. the difference between 2 stick of ddr2 and 4 sticks on a 775 board is a couple notches on the north-bridge/running ram at it's max rated voltage. Or, if you have headroom on the cpu, just crank it's voltage up until the board raises the other voltages to a stable level (would only do this on a cpu at low voltage on a board with limited options though).

More voltage = more heat = lower oc: that's what people mean when they say it limits it. In fairness, unless your case is a shoe box with the cpu at max voltage, it should just be a case of tweaking things until it's all good again.
 
As above, you need to up the voltages and tweak the timings manually. It's unavoidable and even though my mobo (EP45-UD3P) isn't far off from yours and I spent weeks on end finding the goldilocks zone for timings and voltages for NB/SB/VDIMM and CPU as well as the dividers before my 4 sticks of 2GB G.Skill were stable with the CPU heavily overclocked (4GHz Q9550).

Touch wood it's been a year or so now running at these speeds and not a single problem. Put some hard work in and get good rewards from your system :D

I don't know if it helps but running my RAM clocks at 1:1 so once the fsb was OCd the ram freq was not far off from its rated 1GHz helped a lot in terms of stability. The rest was above.
 
Bit of news so far...

All 4 banks stable at 800mhz
All 4 banks stable with the FSB at 333 (3Ghz CPU) and the dimms at 800mhz

So the only difference to now and when this started is the dimms being at 1066mhz and the FSB at 333.
 
Its an all in one fusion unit that runs from a PCIE bridge chip, south bridge, north bridge and then the VRMs. Passive though, so not sure how much I can push it without additional cooling needed.

board_03_t.jpg
 
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