Why some of my RAM is not usable

[hollowman85]

I have an ASUS motherboard with 2X4GB Kingston Ram installed on it.
However, I notice that under the System Tab in the control panel, it was reported that I have 8GB Ram installed, but only 4 GB usable.

How can I find out why the other 4 GB is not usable?
Thanks

Tony

 

[Raiddinn]

I have seen this before the most times when one of the RAM sticks is bad.

Take one out and try to boot the computer. If it works then do the same thing with the other one. I will hazard a guess that the computer won't boot with one of the two and that will be the one that is bad.

If they both work, there are some things in the OS that you can check that I can go into later.

 

[vertical777]

curiously enough, having your cpu cooler on too tight sometimes is the problem, I personally had the same experience, if you know that the sticks are perfectly good (run a few cycles of memtest on them) try loosening your cooler a bit especially if you have an intel cpu, 'cause sometimes the pins lose contact when you have it on too tight.

also don't forget to reseat the DIMMs and CPU before you send the sicks for an RMA as a last resort

have a look at a similar solved problem here

 

[n4v1n]

I have an ASUS motherboard with 2X4GB Kingston Ram installed on it.
However, I notice that under the System Tab in the control panel, it was reported that I have 8GB Ram installed, but only 4 GB usable.

How can I find out why the other 4 GB is not usable?
Thanks

Tony

Install a 64Bit OS instead of 32Bit. 32Bit supports only 4GB RAM.

 

[vertical777]

Install a 64Bit OS instead of 32Bit. 32Bit supports only 4GB RAM.

^this too, I assumed you had a 64bit OS

 

[karthikparys]

If you have a 32 bit Operating system, it can only hold a 4096 MBytes as RAM (this is the max data with 32 0 or 1 bits you can compute mathematically).

Try changing to 64 bit os.

before that ensure if your processor supports it.

 

[smorizio]

it a windows 7 glitch. go under task manger it under one of the tab there check uses full amount of ram. click the box and your error should stop.

 

[mohit9206]

i too have faced this problem..just tried switching the ram slots and it became fine..try it

 

[hollowman85]

it a windows 7 glitch. go under task manger it under one of the tab there check uses full amount of ram. click the box and your error should stop.

Thank you..I've search the task manager but can't find the tab you mentioned.
can you give me a bit more clue?

BTW, I've opened the memory tab in the resource monitor under task manager.
IT show the following:
Hardware reserved: 4099mb
In use: 1828mb
Modified: 59mb
Standby: 1612mb
Free: 594mb

Sound like those ram which cannot be used are being 'reserved'..

Tony

 

[Raiddinn]

Did you do what I told you to?

 

[smorizio]

http://support.microsoft.com/kb/978610

 

[hollowman85]

Hi Raiddinn,
I've followed your suggestion and swapped the RAM... unfortunately the problem presist.
I now suspect the problem could be caused by a faulty motherboard...since the system just reported 4GB during start up...so the problem is not in the Window, which has been smart enough to be able to tell that a total of 8GB had been installed...

Hi smorizio,
thanks for the link.. the info there are very informative..

Tony

 

[Raiddinn]

It sounds to me like one of the sticks is bad and if you run MemTest86+ on each one individually it will be pretty easy to tell which one.

 

[hollowman85]

Thank you Raiddinn, I'll give it a try... but first I need some clarification:
1. do you mean just plugging in one piece (rather than both slot) of Ram at a time and do the memory test?
2. Is the MemTest86+ test the same as the one come with the WIn7 DVD?

Thanks once again..
Tony

 

[Raiddinn]

Yes, run the test with only one of them physically inserted.

Then take it out and do the same for the other one.

I don't know which one you mean that comes with the Windows 7 DVD. I don't remember getting a version of MemTest86+ with any of my Windows 7 DVDs. Most people download it separately online.