Half of memory is not usable - Please help me understand where it is

[pendraggon87]

So here is the short story: I have 4GB of Ram (2x2GB Gskill Ripjaw series) installed. Yet, Ubuntu only recognizes 2GB, Windows recognizes that 4GB is installed, but only 1.99 useable, and the BIOS says that there is 4GB installed. On Windows, running idle, over 1GB of RAM is being used, leaving me with a paltry 1GB left to do anything with. I have an Intel Core i5 750 @2.67Ghz proc and an MSI P55-GD65 mobo, and there is no memory remapping feature. I have an ATI Radeon HD 5750 1GB graphics card.

The RAM is good, I have switched it around, it is in the appropriate channels. Attached are screenshots of performance manager, device manager, and cpu-z. If anyone can help I will sincerely appreciate it! I am VERY bad at converting hex, so am unsure how to read the memory management screenshot, but it should hopefully help identify where all my memory is going.

Additionally, I reran the Windows rating system, and my CPU score dropped from 7.1 to 4.7...is there any way to test if there is now a problem with my CPU? My BIOS settings are Optimized Defaults. I tried generating a system health report, but only the summary would show I could not view any details.

 

[gpost3]

What does BIOS report for total installed memory?
Make sure PAE is enabled in the BIOS (HPET has nothing to do with the issue you have so it can be 32 bit or 64 bit doesn't matter).

Have you tried MemTest86+? Does it indicate 4 GB total installed memory?

Did you check if newer version of BIOS is available?

Each single hex digit is equal to 4 bits (or half byte). It is very clear that the memory address space is 64-bit long in the arrows you pointed out. I can do the conversion for you if you like but not sure if it would help resolve the particular problem you have.

 

[pendraggon87]

BIOS reports 4096MB physical memory. I ran the windows memory diagnostic and it came back with no errors. I ran memtest awhile ago and also no issues. In the arrows I pointed out, I had noticed that the graphics card was reserving two blocks of memory, but I was not sure how large - it shouldn't reserve any. I upgraded BIOS to 1.10, newest available.

 

[logicearth]

Does your BIOS have a Memory Remap feature?

 

[gpost3]

See if you can open up C:\boot.ini and append the following near the end of the file:

/PAE

Save and restart.

 

[logicearth]

See if you can open up C:\boot.ini and append the following near the end of the file:

/PAE

Save and restart.

boot.ini is for previous version of Windows below Windows Vista. Nor is PAE going to have any affect on a 64-bit system.

 

[pendraggon87]

See if you can open up C:\boot.ini and append the following near the end of the file:

/PAE

Save and restart.

boot.ini is for previous version of Windows below Windows Vista. Nor is PAE going to have any affect on a 64-bit system.

Correct - BCDEdit is what is used now. Also, the BIOS does not have any memory remapping feature on it.

 

[gpost3]

Since no one decided to do the math for you, i'll do it for you. Just follow along and let me know if you have questions.

You have 4 GB of memory, your total address space is: 2^32-1=4294967295. To test that answer, Convert that value back into gigabyte 4294967295/(1024^3)=4 GB

I am looking at the second arrow so let's compute the total number of addresses mapped by the ATI Card. We have 8 hex digits which gives us (8x4)=32 bits.

hex code goes from 0-9 then A, B, C, D and so on. So A is 10, B is 11, C is 12 and D is 13 (all in base 10).

13 (Base 10) is 1101 (Base 2). Computing the bits we get 2^31+2^30+2^28=3489660928.
For the second range we have 2^31+2^30+2^28+2^28-1=3758096383.
Difference between the two is 268435455 which is equal to 256 Megabytes reserved by the ATI card.

 

[Layback Bear]

You want to know what is using your ram. Open Task Manager/Performance/Resource Monitor. This is easier, Windows key+ R and type in resmon. It will show you what is using your ram.

 

[stormy13]

Same thing here,

[Solved] P55 SLI not reading 4GB of memory only shows as 2GB

Start with making sure that the heatsink isn't on too tight.. Back off each screw 1/8-1/4 turn, then see if all the memory is available. If that doesn't do it work your way around loosening one screw at a time.

@ gpost3, this isn't as Windows problem at all as he also said Ubuntu only sees 2 GB of the 4 GB.

 

[Layback Bear]

Good point Stormy.

 

[pendraggon87]

You want to know what is using your ram. Open Task Manager/Performance/Resource Monitor. This is easier, Windows key+ R and type in resmon. It will show you what is using your ram.

It just says Hardware Reserved for 2GB, does not say what is using it. I discovered through some other resources on the system that going into the system information I can view each device and the range of memory it is using. One of the earlier posts did the math for me there.

However, I am unsure why my graphics card, which should have 1GB on the card, is using 2GB of my RAM...

 

[pendraggon87]

Same thing here,

[Solved] P55 SLI not reading 4GB of memory only shows as 2GB

Start with making sure that the heatsink isn't on too tight.. Back off each screw 1/8-1/4 turn, then see if all the memory is available. If that doesn't do it work your way around loosening one screw at a time.

@ gpost3, this isn't as Windows problem at all as he also said Ubuntu only sees 2 GB of the 4 GB.

While it may seem that Ubuntu was having that problem also, the problems seem slightly different. Ubuntu didn't even recognize the other 2, but I never really use it except when windows craps up. Windows however will recognize the other two, but as gpost3 discovered, my graphics card is using up 2GB of my RAM...extremely annoying. I will try your heatsink suggestion when I get home. I stupidly put in a monster of a heatsink that makes cable management a nightmare, and need a new fan as well, so much to do...

 

[stormy13]

You would be surprised how often what you're experiencing happens when the heatsink is on too tight,

http://www.sevenforums.com/hardware...ws-7-x64-not-recognizing-ram.html#post1182684

 

[Layback Bear]

Go right above that colored bar you are looking at to processes and it will show you what and how much ram is being used for what. I don't use Ubuntu. You can use Windows 7 all by it's self to see a lot of things.

 

[gpost3]

I don't buy that the heatsink will cause software to malfunction. I think there is a confounding variable here which was fixed while the heatsink was being replaced. It is like the old days when they used to say that coffee is a potential cause of lung cancer but later discovered that people who smoke tend to drink a lot of coffee (and smoking was causing lung cancer). Try the heatsink idea but it sounds stupid to me.

 

[pendraggon87]

Go right above that colored bar you are looking at to processes and it will show you what and how much ram is being used for what. I don't use Ubuntu. You can use Windows 7 all by it's self to see a lot of things.

In Windows, it says 2GB hardware reserved. I cannot trace where that is in resource monitor or performance monitor. In Ubuntu, it ONLY registers that I have 2GB of RAM.

 

[stormy13]

I don't buy that the heatsink will cause software to malfunction.

Who said anything about software? It has also been confirmed that mounting the heatsink too tight can cause the same issue that pendraggon87 is having. now as far as stupid, might want to take that up with these guys,

RAM Problems? Cooling too Tight? - [H]ard|Forum

Troubleshooting Thread for Incorrect Memory Amounts on X58 and P55/H55/H57 Platforms - The Corsair Support Forums

and just in case you don't like links, this is from the link on the Corsair forums (and no the big red text isn't my doing),

Also, be sure to inspect your CPU cooler mount. Over tightening or unequal pressure on the CPU socket can cause the CPU to not seat correctly. Frequently, this translates into what appears to be memory related problems because the CPU/IMC is not making proper contact with the pins leading to the memory sockets. The fundamentals here apply to systems with 3 modules also and especially when overclocking. This applies to P55/H55/H57 also. In any situation where you have these issues and where the above steps do not work, please remove your CPU and inspect the socket for bent pins

which makes it even more fun in that you can possibly bend pins in the socket due to over tightening.

 

[gpost3]

pendra, have you tried running the RAM in single channel mode? And also see if you can take your system to a friend's place and borrow/test his memory on your machine.

 

[Layback Bear]

Lets keep it a little less Kick you in the xxxx. We all want to learn and help. Questions; can ram be seated wrong; answer yes, please check. Can the M/B have a problem, yes please check this or that. We all do this. We are all on a WINDOWS 7 forum to try and help people using Windows 7 if at all possible. Every thing you see here may or may not help but who ever posted it meant well. If some one thinks another O.S. is better that's okay. Why are you here? If Ubuntu gives you information you like I'm sure they have a web site. Many people here leave instruction of how to use Ubuntu to help with problems and we use them and say thank you. Or don't use them and say thank you, it's your computer you choose. To the best of my little pea brains knowledge their is no operating system that suites every body in every way. Work with us and we will work with you!!!! Layback Bear.