Why is Win 7 only accepting 3 sticks of memory

I have been unable to get Windows to accept a memory upgrade. I want to increase my memory from 4Gig to 8Gig (ie 2 sticks of 2Gig, to 4 sticks of 2 Gig). Windows hangs with all 4 sticks installed, but boots normally with only 3 sticks installed ?

It seems that the BIOS is happy to accept 4 sticks x 2Gig ... but Windows hangs: With all 4 sticks installed The BIOS will boot and the Windows boot screen appears (the four star animation) ... and then the system hangs !

By a process of elimination, I have been able to deduce that none of the individual sticks, or the individual slots are faulty: I can use any combination of 3 sticks in any combination of the four available slots, and it will boot OK and show 12 Gig of memory available.

I have checked that all 4 memory sticks are identical (Corsair Vengeance 1600mhz DDR3), and I have downloaded and installed the latest BIOS ... but the problem persists.

I note that the 2 original memory sticks are labelled V.2.12 and the second pair are labelled V.3.19, but I also note that they are happy running together as long as I only use 3 sticks (any 3 sticks !). The problem only arises when I try to use all 4 !!


Can anyone help

Just passing by

What is the max memory set to in msconfig?

start>search>cmd>msconfig

Hello handygrandad and welcome to Seven Forums.

It sounds like you have already verified all the hardware is OK...good work...

Sometimes adding more ram can require a bit more voltage above stock to work correctly.
That would be a Ram Voltage setting change in your BIOS.
If you do this, go slowly...bump voltage up 1 step at a time and test it.

You could also try changing the Ram speed down from 1600 with 4 sticks, and see if that helps.
This change is "safer" as you can't "over volt" and hurt anything...

I've seen 4 sticks have problems solved with both of these approaches.

Without looking up your MB/BIOS documentation, I'm not sure what your system can change.
Based on your specs (Custom Build), I'm guessing you are familiar with this...

Let me know if you have questions and i'll look for your MB doc.

zigzag3143 said:

Just passing by

What is the max memory set to in msconfig?

start>search>cmd>msconfig

Hi ZigZag,

I've checked msconfig ... Under Boot tab > Advanced options ...

If I tick the "Number of processors" box I get "1" ... (I am using an Intel i5 - 4 core processor).

If I tick the "Maximum memory" box it shows 12,288



I am a little out of my depth here so I would be grateful for your guidance before I make any changes that might lock me out completely.


Is it just a case of altering these entries ?

Is it "safe" to experiment (i.e. to try alternative entries)

Does the "Number of processors" refer to the CPU or the number of cores?

Assuming that altering these entries may resolve my problem ... ... Would you know if there is any advantage/disadvantage in entering 33,000 for maximum memory (to reflect the potential physical limit for my MB) ?

Many thanks for your prompt response ... it looks like you may have found the cause of my problem.

DavidW7ncus said:

Hello handygrandad and welcome to Seven Forums.

It sounds like you have already verified all the hardware is OK...good work...

Sometimes adding more ram can require a bit more voltage above stock to work correctly.
That would be a Ram Voltage setting change in your BIOS.
If you do this, go slowly...bump voltage up 1 step at a time and test it.

You could also try changing the Ram speed down from 1600 with 4 sticks, and see if that helps.
This change is "safer" as you can't "over volt" and hurt anything...

I've seen 4 sticks have problems solved with both of these approaches.

Without looking up your MB/BIOS documentation, I'm not sure what your system can change.
Based on your specs (Custom Build), I'm guessing you are familiar with this...

Let me know if you have questions and i'll look for your MB doc.

Thanks for the warm welcome ... ...

It looks as though ZigZag may have identified a possible reason why windows is rejecting 4 sticks (ie 16Gig). I have decided to pursue this until I can establish whether it makes a difference or not ... ... then I may start adjusting the BIOS entries.

Thanks for the prompt response

Will keep you posted on developments

logicearth said:

In msconfig and those advance options those checkboxes MUST be unchecked.

Thanks for the "heads up"...

Luckily, I am pre-disposed to put things back as I find them ... so no harm done this time !

NB I have noticed a significant error in my original posting ... I am actually increasing memory from 8Gig (2 x 4Gig), to 16Gig (4 x 4Gig)

So, the figure that appeared in mscongig of 12,288 seems relavent, if not a strange coincidence.

Can you throw any more light on this ?

You need to find your original motherboard specifications and see what is the best memory compatibility for working with your BIOS and the motherboard itself. I have found that although Corsair memory works okay Kingston sometimes is better, FYI.

First I would not have bought memory sticks that had different voltage settings. I would have made sure that the voltage settings were the exactly the same from the memory I was introducing or replacing. I would stick with the 2.12 volts. The reason why the three sticks are working fine is because the BIOS is lowering the voltage of all three sticks for compatibility reasons.

If the BIOS cannot recognise all 16GB then changing the settings under windows is USELESS!

Keep in mind that some motherboards have a cap on the amount of memory that can be installed on one motherboard. Although the motherboard may accept 16GB of memory in total, the way it is introduced to the system will have an effect on how the BIOS will read the memory sticks and calculate the amount of memory. For example, you motherboard may cap, totally at 16GB but you might want to introduce the total 16 GB as (2) 8GB DDR2 1600 sticks, rather than (4) 4GB DDR2 1600 sticks, for example...

Also, most motherboards will share memory with your integrated video card, keep this in mind, too.

By the way.....

I looked again and it looks like you are sharing main memory with your video card...

If you take your memory 16GB * 1024MB = 16384MB minus the 12288MB (or 12GB) equals 4096MB or 4GB...

That 4GB looks like BIOS is introducing that memory to your internal video card. In other words, you have an integrated video card that needs 4GB of system memory because it has no video RAM to use so it utilizes the system memory.

Also, on your motherboard is your memory slots different colors? IE - 2x Black and 2x Blue, or whatever? Then try pairing your voltages. Since you have memory that differs only in voltages try pairing the 2.12 voltage sticks together and then the 3.19 voltage sticks together. (I still would not recommend using different voltages but since you already have them it is worth a try since you told us that any three memory sticks will work and be recognised on your MB and in your BIOS.)

Also, I have used ZigZag, but I have found that CPU-Z Validator works a little better. I have Kingston memory in my notebook, for example, but one 2GB-bank is made by Kingston themselves and another (although it is stamped Kingston on the outside) is actually made by Hyundai Electronics.

Again, the easiest way is to find your motherboard documentation and read it to find the best way to introduce how you are going to utilize all of the 16GB of the memory cap for your system. Since you have 4 DDR2 slots does not mean that you need to utilize all of them. Sometimes utilizing just two of them will be better and produce better results than utilizing all four. (Plus it will determine what your pocket book says buying (2) 8GB DDR2 1600 stick of memory can be more expensive than purchasing (4) 4GB DDR2 1600 memory sticks.)

Hope this helps...

Cheers!

First I would not have bought memory sticks that had different voltage settings. I would have made sure that the voltage settings were the exactly the same from the memory I was introducing or replacing. I would stick with the 2.12 volts. The reason why the three sticks are working fine is because the BIOS is lowering the voltage of all three sticks for compatibility reasons.

This memory is 1.5 volts.
V.2.12 and V.3.19 in the OP do not represent Volts.
My guess is that is a version number, revision number, ...

DavidW7ncus said:

First I would not have bought memory sticks that had different voltage settings. I would have made sure that the voltage settings were the exactly the same from the memory I was introducing or replacing. I would stick with the 2.12 volts. The reason why the three sticks are working fine is because the BIOS is lowering the voltage of all three sticks for compatibility reasons.

This memory is 1.5 volts.
V.2.12 and V.3.19 in the OP do not represent Volts.
My guess is that is a version number, revision number, ...

That is what I thought ...

i just took his word for it...that is all...