Hi everyone--

I've been having this problem for a while but forgot about it until just now.

I am currently having an issue with my PC, where it is not recognizing the full amount of installed RAM. I have 16GB of DDR3 RAM (4 4GB sticks) in my ASUS motherboard, but according to my computer properties, it only has 8GB:



I do have CPU-Z installed, and it actually sees the full 16 gigs:



Anyone have any idea what's going on? Have any of you folks had this problem before, and how might I go about fixing it? I've re-seated the RAM already and it had no effect.

Thanks guys!
Matt

 

I should mention that when I first installed the RAM it did show up as 16GB, but I had to dismantle my PC for an unrelated problem, and when I put it back together it only recognized half.

 

Not sure.

Try cleaning contacts on the sticks.
Try resitting them.

 

Not sure.

Try cleaning contacts on the sticks.
Try resitting them.

I tried both of those a while ago and had no success. It's not a problem with the cards not making full contact, otherwise it most likely wouldn't show up correctly in CPU-Z or SWI (which I also used), where it actually does.

My guess is that the system does in fact recognize it, it simply doesn't show up correctly in the computer properties window. I'm just trying to figure out why.

 

I tried both of those a while ago and had no success. It's not a problem with the cards not making full contact, otherwise it most likely wouldn't show up correctly in CPU-Z or SWI (which I also used), where it actually does.

My guess is that the system does in fact recognize it, it simply doesn't show up correctly in the computer properties window. I'm just trying to figure out why.

Does the chipset on the mobo support 16 GB?

I ask because I have an older board that support 8 GB max. I have 4 GB currently in it.

 

I fixed this problem in 2 of my computers and another one from a friend, and all 3 times it was a stick making a bad contact; but, since you say this is not the problem you might want to check the memory section on the bios screen and see which memory banks are detected. If all banks are detected by the bios then it's an OS problem; if not, then either a stick or a memory channel might not be working. In which case, take all sticks out and try them separately (first on channel A, and then on both).

 

Does the chipset on the mobo support 16 GB?

I ask because I have an older board that support 8 GB max. I have 4 GB currently in it.

The chipset supports up to 24GB. And as I mentioned, it did show up originally, when I first installed the RAM.

I fixed this problem in 2 of my computers and another one from a friend, and all 3 times it was a stick making a bad contact; but, since you say this is not the problem you might want to check the memory section on the bios screen and see which memory banks are detected. If all banks are detected by the bios then it's an OS problem; if not, then either a stick or a memory channel might not be working. In which case, take all sticks out and try them separately (first on channel A, and then on both).

I remember looking in the BIOS to see what was shown, but I can't remember if it showed the full 16 or just the 8. I'll have to do that again this afternoon after work.

 

Maybe one died? Have you tried putting each in at separate times and tried to boot? That will allow you to rule out faulty RAM, at least...

EDIT: Sorry, Adam, looks like I should have read your post before suggesting the same thing...

 

Maybe one died? Have you tried putting each in at separate times and tried to boot? That will allow you to rule out faulty RAM, at least...

I considered that, but the fact that all programs except the system (which populates the computer properties window) seem to recognize all the cards as they should suggests that all the cards are ok. I'll see about trying it anyway though, after checking what the BIOS shows.

 

I considered that, but the fact that all programs except the system (which populates the computer properties window) seem to recognize all the cards as they should suggests that all the cards are ok. I'll see about trying it anyway though, after checking what the BIOS shows.

How do you know all programs are using the 16Mb? (I'm asking)

Take into account that even if you have a faulty channel (which is rare) or a faulty memory stick/connection (which is very common), everything could perfectly would work as before; the only difference is that you would only be using half the memory. Also take into account that you might not notice the missing memory with your programs, as windows will compensate with the virtual memory. You would only notice it in terms of speed, and only with programs that use more than 8Mb of physical memory.

The only way to be sure is looking at your BIOS, you should see each bank of each channel detecting 4Mb.

 

How do you know all programs are using the 16Mb? (I'm asking)

By "programs" I mean ones like CPU-Z and SWI (maybe it's SIW, I can't remember), which monitor the system's information. They all show 16GB installed. The only thing that doesn't is the built-in properties window.

 

I see...

I think I had a similar problem years ago, when the System Properties window showed less memory than it should; but I can't remember now exactly why it did or how I fixed it.

If those programs state 16Mb, I'm pretty sure the BIOS will also show that amount; which means there's nothing physically wrong.

 

I see...

I think I had a similar problem years ago, when the System Properties window showed less memory than it should; but I can't remember now exactly why it did or how I fixed it.

If those programs state 16Mb, I'm pretty sure the BIOS will also show that amount; which means there's nothing physically wrong.

Thanks adam. That's what I was figuring, but just wanted to see if anyone knew why Windows wasn't showing the full amount.

Cheers,
Matt

 

If your board has dual processors in it, the machine may see both banks but it will need two co-pro's to actually make use of it. I'm thinking of the HP xw series for example. The board may also be limited to 8 megs max.

Michael Lalonde <SNIP>
Sudbury, Ontario

 

If your board has dual processors in it, the machine may see both banks but it will need two co-pro's to actually make use of it. I'm thinking of the HP xw series for example. The board may also be limited to 8 megs max.

Michael Lalonde <SNIP>
Sudbury, Ontario

I thought of that as well, but my board is slightly older, with only a single slot for an LGA 1366 processor. Previously, when I first installed the RAM, all 16GB showed up in both CPU-Z and in the computer properties window, but then I did something (I can't remember if it was when I rebuilt the machine or if I just unplugged it and moved it), but after that it no longer showed up as 16. I reseated the RAM several times with no change, and considering it still shows up in CPU-Z (and the bios), I expect the actual RAM and RAM position isn't a problem.

 

I know that my computer has 8 GB RAM physically installed, but Windows 7 Home 32 bit can only use 6GB, and that is all it will show.

 

I use Windows 7 professional x64, so it can use as much RAM as is installed.

I guess I forgot to post it here, but I think my problem was that my BIOS was out of date. I updated it and after a bit of a scare (bad boot) the full 16GB was visible.

I eventually had another problem, the computer would cycle every time I turned it on--it'd switch on, shut off immediately, turn on again, shut off again, and finally start up and POST the third time. After some further tweaking and testing I discovered one of my 4GB sticks was bad (it hadn't shown up as bad on any of the other tests I ran, but when I ran memtest86 a fault showed up almost immediately). I removed the bad stick and it's been running like a dream ever since, though video editing software and some high-demand programs lag a bit with only 12GB. I'll probably buy a couple more sticks eventually (since they should be bought in pairs), but I'm not in a huge hurry.

Thanks for the replies everyone, and I hope someone can benefit from this post in the future.

Regards,
Matt

 

I know you had already resolved this, but in the msconfig, you can set the available memory size...Check your msconfig, make sure that max RAM size is enabled.



or check this out >>
http://support.microsoft.com/kb/978610

 

I know you had already resolved this, but in the msconfig, you can set the available memory size...Check your msconfig, make sure that max RAM size is enabled.

View attachment 64352

or check this out >>
http://support.microsoft.com/kb/978610

I'll have to check that next time I'm logged in to my desktop. I can't imagine the BIOS update changed that, but I suppose it's possible?

Interesting nonetheless, thanks for sharing!

Matt

 

I'll have to check that next time I'm logged in to my desktop. I can't imagine the BIOS update changed that, but I suppose it's possible?

Interesting nonetheless, thanks for sharing!

Matt

Actually in the second link I posted, says that updating your BIOS could be one solution to resolve this issue