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Vandelay
24-01-2012, 10:51 PM
I've just received an additional 2 sticks of 2GB G-Skill DDR3 1600MHz Ripjaws RAM, to go with the two that were already in my computer, making a total of 8GB of RAM. After plugging this in and confirming that all was good in the BIOS, I boot my computer. Everything seemed fine, until I glanced at the performance tab on the Windows task manager, which told me I still only had 4078MB of physical memory. I've double checked that the RAM is correctly slotted into the motherboard and also the hardware monitor CPU-Z has confirmed that all four sticks are present and totalling 8192MB of memory, but Windows refuses to acknowledge the existence of these extra RAM sticks.

I've had a glance around the Internet for any possible solutions for an issue like this, but not found anything that isn't to do with someone not knowing they need 64-bit Windows or altering some setting in your BIOS, that I do not seem to have (memory remapping, I believe.) Others have also mentioned the pins of, I presume, the RAM being slightly bent, but it seems strange that both my BIOS and CPU-Z would be detecting it without any problems, as well as the memory test on the BIOS picking up no error. It certainly seems like an issue with some setting in Windows to me and my limited computer tech knowledge.

Anyone have any ideas? Probably relevant computer specs are:

MSI P67A-C45 motherboard
Intel Core i5 2500K
8GB G-Skill DDR3 1600MHz Ripjaws
Windows 7 64-bit Professional

Here is a screenshot of the information about one of the memory slots from CPU-Z, if this means anything to anyone. All the slots have the same information:

647

vecordae
24-01-2012, 11:12 PM
I'm going to cover the things I can think of off the top of my head. Some may sound stupid, but are included for the sake of completeness.

1) You are using a 32-bit rather than a 64-bit installation of Windows 7.

2) Your two new memory sticks aren't running at the exact same clock speed as your older ones. Try removing the older stuff entirely or leaving one stick in while moving your new ram to the old ram's slots on the motherboard.

3) Your windows 7 is running on a 32-bit shell for some reason. Do you have windows XP mode turned on?

4) You have overclocked your system to the point where the new ram isn't able adequately keep up. Try running your computer at its default speeds to see if the new ram will play nice.

5) You have offended Xango the Yoruba god of lightning and he has responded to your slights by screwing with your electrons.

Rakysh
24-01-2012, 11:17 PM
If it's the last one, you need to sacrifice a Gameboy Colour up a mountain quicksharp.

Vandelay
25-01-2012, 12:03 AM
I don't recall offending any gods recently, but there have been many times in the past...

If I was running in 32-bit shell or Windows XP mode (don't know how I would even do that, so unlikely), would it not have maxed the RAM at 3.something? I thought 32-bit was less then 4GB maximum?

Not got anything overclocked and everything is set to the same speeds as when I bought the components. RAM is exactly the same as I original bought, even from the same retailer, so there shouldn't be any difference in clock speed there. As I say, CPU-Z shows identical information as the above screenshot for all the slots. Although I don't really know what the frequency, CAS# Latency, RAS# to CAS', etc all means, I'm assuming it means the settings should all be the same.

vecordae
25-01-2012, 12:24 AM
The next thing to check is the bios memory settings. I can't find a screenie of your bios' setup screens, but if you can poke around in there and tell me what you find, we may be able to figure out what the problem is.

FuriKuri!
25-01-2012, 10:50 AM
http://support.microsoft.com/kb/978610

Vexing Vision
25-01-2012, 11:24 AM
I was having the same problem, and finally identified the issue: a technical failure of my motherboard was unable to address two of the RAM slots.

Feldspar
25-01-2012, 06:57 PM
I'd play the RAM removing game; see if it boots with just the new RAM in, switch the new RAM to where the old RAM is currently sitting, etc. Tedious, but it should show you if it is the motherboard having duff slots or if you have duff RAM sticks.

Vandelay
25-01-2012, 11:00 PM
Just tried taking out my old RAM and leaving the new sticks in slots 2 and 4. Works absolutely fine, so that eliminates any hardware issue with the sticks or the motherboard.

Looking around the bios options I can't find anything that might help, particular not the memory remapping option that I've seen mentioned elsewhere (funnily enough, typing my motherboard and memory remapping into Google provides this thread as the top result!) Only options concerning memory seem to be overclocking. I have noticed that my current bios version is quite out of date though, so might try updating that. Multiple updates mention improved memory compatibility and modules.

SMiD
25-01-2012, 11:04 PM
Absolutely check for relevant BIOS updates. I've been running your problem through my head and co-workers' and BIOS was mentioned a few times. Let us know how it goes.

Duckee
26-01-2012, 01:14 AM
I had the same problem with my 6 sticks of 1gb ram for ages too, in win7 64 bit. I did not think too much about it other than being annoyed with it and not finding any viable solutions to it too, which made me just forget about it and hoping that it was some wierd power saving feature or something. However, recently for reasons unknown to me all 6 sticks are now active without me doing anything in particular. The only thing I have done when I think about it was refit my heatsink and change paste.

Not very useful info I am afraid, but there we are.

psythrone
26-01-2012, 08:56 AM
You could have a bent pin on your CPU, that can stop your computer from properly using your ram.

You can also check if you have a ram limit on system boot;
1. Press start
2. Write msconfig
3. Press enter
4. Go to "Boot" tab
5. Select currently running windows installation and press "Advanced options..."
6. Make sure "Maximum memory:" isn't checked.

Also, anyone else having this problem but with a slightly older CPU/mobo combo (specifically I7 920 and any x58 based mobo) should know that there are barely any 1333Mhz (or faster) sticks that will be read properly, which I learned last friday.

Vandelay
26-01-2012, 10:45 PM
Thanks for everybody's help. Turns out that updating the bios did actually work. I now have the full 8GB being used by Windows.

KilgoreTrout_XL
26-01-2012, 10:50 PM
You could run memtest86+ on them to see if they were working properly, though with 4 dimms it would take kind of a while. http://www.memtest.org/

Is the older set in D1 and D3, and the new stuff in D2 and D4? Go in into your BIOS and try to force it all to run at 1333.

I wonder if your new stuff is set at 1600 and your old ram isn't. You don't get much out of running them that hot, and your DRAM voltage is a little low for it right now anyway- I'm told you need about 1.65v for it, but I think it's mostly a good way to break something.

vecordae
26-01-2012, 10:56 PM
Good to hear, man! I'll definitely remember that solution next time I bump into the problem.