Windows 7: Only half my memory being used

BadGuy · 18 Oct 2009

Hey guys, I just upgraded my mainboard (and processor/memory etc) due to my old mainboard having a its SATA2 controller fried. So I set out to go and buy some of this new stuff and I ended up with:

ASRock P55 pro mainboard
QuadCore Intel i5 750
4GB of ram (2x 2GB)

Now obviously this is dual channel memory so I used the A1 and B1 banks (as suggested by ASRock's manual), and I also have Windows 7 64-bit. Now the thing is. Windows 7 reports that only 1.99 GB of the 4 GB can be used. Lavalys Everest tells me a similar story:

Code:

 Motherboard:  
   CPU Type   QuadCore Intel Core i5 750, 3033 MHz (23 x 132)  
   Motherboard Name   ASRock P55 Pro (2 PCI, 2 PCI-E x1, 2 PCI-E x16, 4 DDR3 DIMM, Audio, Gigabit LAN, IEEE-1394)  
   Motherboard Chipset   Intel Ibex Peak P55, Intel Lynnfield  
   System Memory   2039 MB (DDR3-1333 DDR3 SDRAM)  
   DIMM1: RMB2GB484CA6-13HC   2 GB DDR3-1333 DDR3 SDRAM (9-9-9-24 @ 666 MHz) (8-8-8-22 @ 592 MHz) (7-7-7-19 @ 518 MHz) (6-6-6-16 @ 444 MHz)  
   DIMM3: RMB2GB484CA6-13HC   2 GB DDR3-1333 DDR3 SDRAM (9-9-9-24 @ 666 MHz) (8-8-8-22 @ 592 MHz) (7-7-7-19 @ 518 MHz) (6-6-6-16 @ 444 MHz)  
   BIOS Type   AMI (08/05/09)  
   Communication Port   Communications Port (COM1)

My bios also report that I have 2x 2 GB of memory in there and a run of DXdiag also shows 4gigs.

Does anyone have any idea on how to fix this? Or is this normal behaviour?
[edit]
I changed my memory around to use slots 1 and 2 instead of 1 and 3 and now it uses 4 GB, but it's (obviously?) single channel mode. My question still stands though is it usual for windows 7 in dual channel mode to 'only' use half of the memory available? Also I noticed that the bios registered the memory, but during POST it only showed 2GB before. Right now it's 4 GB. The problem isn't 'solved' yet though, I'd like to use the dual channel capabilities

.
[/edit]

sup3rsprt · 18 Oct 2009

did you clean install Windows with the new motherboard?

do you have the latest BIOS, drivers, and all that good stuff?

BadGuy · 18 Oct 2009

Quote: Originally Posted by sup3rsprt

did you clean install Windows with the new motherboard?

do you have the latest BIOS, drivers, and all that good stuff?

Yeah I just got started on updating BIOS etc. Windows is a clean installation too. I updated all of my drivers as well. From the reactions I'm getting so far is that this isn't the usual behaviour even when using dual channel memory mode.

sup3rsprt · 18 Oct 2009

Quote: Originally Posted by BadGuy

Also I noticed that the bios registered the memory, but during POST it only showed 2GB before.

If POST only shows 2GB when both sticks are installed, that is not a Windows 7 problem.

Are both of the memory sticks and SPD settings/timings identical?

BadGuy · 18 Oct 2009

Quote: Originally Posted by sup3rsprt

Quote: Originally Posted by BadGuy

Also I noticed that the bios registered the memory, but during POST it only showed 2GB before.

If POST only shows 2GB when both sticks are installed, that is not a Windows 7 problem.

Are both of the memory sticks and SPD settings/timings identical?

Yes, I did not change any settings on the memory. I'm not really blaming Windows 7 though, I'm just hoping someone can help me trouble shoot this thing. Going through the bios I see both DIMMs with the same settings just in different slots. The bios screen shows them both properly as I mentioned before. I've not really found any settings regarding my memory (except OC-related settings), that I could perhaps mess with either. It all seems a little weird to me and I just can't fill out the gaps between both pieces of memory showing in the bios, and only half the memory being checked as available during POST.

The memory was bought along with the board and processor in the same shop. The only difference that I can find between the two dimms are the manufacturing dates (they're 3 weeks apart

), otherwise they're identical.

I'm still trying to update my BIOS, but I've only gotten so far since ASRock seems to have some weird utility that just won't work (and is very poorly documented). None of the fixes listed in the bios upgrades seem to relate to memory though.

sup3rsprt · 18 Oct 2009

Quote: Originally Posted by BadGuy

The only difference that I can find between the two dimms are the manufacturing dates (they're 3 weeks apart

), otherwise they're identical.

Did the memory modules come in the same package, brand new, unopened and untampered with? If not, it could be your problem. Memory has to be paired correctly for it to work as dual channel.

According to information in your first post, the memory's SPD timings do appear to match.

Try to find a chart that shows supported memory modules for your motherboard. Sometimes RAM just isn't compatible.

sup3rsprt · 18 Oct 2009

Also,

Can you clear up whether or not your system (BIOS/POST) actually detects the full 4GB when in dual channel mode? As I'm confused by your statement

Quote:

It all seems a little weird to me and I just can't fill out the gaps between both pieces of memory showing in the bios, and only half the memory being checked as available during POST.

BadGuy · 18 Oct 2009

I found a chart and I don't see the memory listed (I think it's just generic branded), the chart only shows tested memory rather than actual compatibility. So it's rather inconclusive, I'll go a head and give the guys at the shop a ring and tell them about this stuff and we'll see if they do have some compatible RAM. The speed increase shouldn't be that much according to reports, but it's still good to use the full potential of your new gear

.

Thanks for the help and pointers so far, I'll keep you posted if I learn anything new tomorrow.

As for the question:
POST shows 2 GB (Dual Channel Mode)
Going in to the BIOS it shows both DIMMS at 2 GB (so 4 in total)

I've changed the banks the DIMMS are seated in to force single channel mode:
POST shows 4 GB (Single Channel Mode)
Going in to the BIOS it shows the same as before, but the memory is loaded in to different banks ofcourse

zigzag3143 · 18 Oct 2009

Quote: Originally Posted by BadGuy

Quote: Originally Posted by sup3rsprt

Quote: Originally Posted by BadGuy

Also I noticed that the bios registered the memory, but during POST it only showed 2GB before.

If POST only shows 2GB when both sticks are installed, that is not a Windows 7 problem.

Are both of the memory sticks and SPD settings/timings identical?

Yes, I did not change any settings on the memory. I'm not really blaming Windows 7 though, I'm just hoping someone can help me trouble shoot this thing. Going through the bios I see both DIMMs with the same settings just in different slots. The bios screen shows them both properly as I mentioned before. I've not really found any settings regarding my memory (except OC-related settings), that I could perhaps mess with either. It all seems a little weird to me and I just can't fill out the gaps between both pieces of memory showing in the bios, and only half the memory being checked as available during POST.

The memory was bought along with the board and processor in the same shop. The only difference that I can find between the two dimms are the manufacturing dates (they're 3 weeks apart

), otherwise they're identical.

I'm still trying to update my BIOS, but I've only gotten so far since ASRock seems to have some weird utility that just won't work (and is very poorly documented). None of the fixes listed in the bios upgrades seem to relate to memory though.

BG

Dont mean to jump in here but does your bios have a setting for max memory? whats it set at?

sup3rsprt · 18 Oct 2009

Quote: Originally Posted by zigzag3143

Dont mean to jump in here

At this point we need all the help we can get

Interesting about this "max memory" setting. I don't think any of my systems have it.

Windows 7: Only half my memory being used

Only half my memory being used problems?