PDA

View Full Version : PC rebuilt - missing memory?



Jayess64
27-06-2011, 08:34 PM
About a month ago I rebuilt my desktop: Gigabyte GA-P67A-UD4-B3, 2x2GB DDR3 RAM. All seems to run OK, but I have noticed that the POST reports only 4080GB RAM, 16MB short. If I remove one stick at a time, POST shows 2032GB both times - once again 16MB short.

I have just run Memtest from the current PCW DVD. It gets through all tests without any errors, but it reports 4079GB total memory.

Do I have a problem, or is there something going on that I don't know about?

Greven
27-06-2011, 08:42 PM
does your board have onboard video?

Jayess64
27-06-2011, 10:30 PM
does your board have onboard video?

No, I think that's the H67 board. I'm using a GeForce 9400 GT. Pretty feeble, I know, but OK for what I want. The MB does have on-board audio but I wouldn't have thought they would reserve that much RAM (could be wrong).

I should have mentioned the CPU is a Core i5-2400 and the RAM modules are
both Corsair XMS CMX4GX3M2A1600C8., DDR3-1333 according to Aida64 (which also reports 4079GB)

Speedy Gonzales
27-06-2011, 10:35 PM
Is it 32 or 64 bit windows?

Jayess64
27-06-2011, 10:43 PM
Is it 32 or 64 bit windows?

64-bit Win 7 Premium. But does the POST know that?

Speedy Gonzales
27-06-2011, 10:52 PM
Is there an option in the BIOS similar to memory remap feature?? If there is, is it enabled?

Jayess64
27-06-2011, 11:25 PM
Is there an option in the BIOS similar to memory remap feature?? If there is, is it enabled?

Getting past the limits of my competence here, but as far as I can see there isn't an option along the lines you suggest. However, the BIOS menu does have an entry headed 'MB Intelligent Tweaker' - this is an area I normally keep well away from. When I look into here, I see that the memory reported is what I would expect, 2 x 2048MB = 4096MB.

So, a thought occurs: can it be that at startup the BIOS loads something into RAM that stays resident, and it is the available RAM that is being reported? If that is right, I should shut up and stop wasting everyone's time.

But I wouldn't have thought of this without having my brain cells tickled by Greven's and Speedy's suggestions.

Speedy Gonzales
27-06-2011, 11:42 PM
What slots did you put the ram in?

This may or may not help

http://www.xtremesystems.org/forums/showthread.php?264909-******Gigabyte-GA-P67A-UD4-Discussion-Thread******

Jayess64
28-06-2011, 12:30 AM
What slots did you put the ram in?

This may or may not help

http://www.xtremesystems.org/forums/showthread.php?264909-******Gigabyte-GA-P67A-UD4-Discussion-Thread******

I haven't had the hassles that some of those guys had. The manual for the GA-P67A-UD4-B3 is clear about the slots you should use for Dual Channel RAM, and I have followed their recommendation. It looks as though the situation may be different for the -UD4 & the -UD4-B3 boards.

For the moment I am inclined to stick with my guess that I am seeing available RAM, not physical RAM. Interestingly, when I run Aida64 on my brand new Asus X73SV laptop (also a Sandy Bridge MB), it reports 4008MB RAM, even though the BIOS shows 4096MB. Some of that may be shared RAM for video, as Greven suggested. I suppose it all means that you should interpret the numbers you see with some caution.

Thanks for your comments.

pctek
28-06-2011, 08:27 AM
So, a thought occurs: can it be that at startup the BIOS loads something into RAM that stays resident, and it is the available RAM that is being reported?


No. Even if it was - you still see total RAM. Have a look in the BIOS and see if there is anything to do with onboard graphics being used, that will be what it is. Make sure you have it choose to look for add-on card first, there's usually an option. It shouldn't matter, but try it and see what happens.

Jayess64
28-06-2011, 11:03 AM
No. Even if it was - you still see total RAM. Have a look in the BIOS and see if there is anything to do with onboard graphics being used, that will be what it is. Make sure you have it choose to look for add-on card first, there's usually an option. It shouldn't matter, but try it and see what happens.

There is no mention of on-board graphics in the manual or the BIOS settings. It's my understanding that the P67 boards don't have that feature, but you get it on the H6x & Z68 series boards. No graphics connectors on the back-plane, either.

In a previous response to Speedy Gonzales I mentioned that if I went into the 'Motherboard Intelligent Tweaker' page in the BIOS I could see the RAM reported as 2 x 2048 = 4096GB. The number reduces after POST starts but before Windows loads, and stays at that value when I use Aida64. It also seems curious that the reduction (16MB) is the same whether I have both or only one RAM module installed.

The only other feature about the system is that sometimes - not always - there is a pause of up to 30 sec before POST starts running, but the values it reports are always the same. Since the system otherwise seems to run properly I am beginning to wonder if I am chasing shadows.

I appreciate the different comments that I have had about the situation - they confirm my impression that this one of the best get-help-quick forums around.

Agent_24
28-06-2011, 11:15 AM
Maybe it's a BIOS bug. I would contact Gigabyte about it, they might release an update to fix the problem.

ManUFan
28-06-2011, 01:21 PM
About a month ago I rebuilt my desktop: Gigabyte GA-P67A-UD4-B3, 2x2GB DDR3 RAM. All seems to run OK, but I have noticed that the POST reports only 4080GB RAM, 16MB short. If I remove one stick at a time, POST shows 2032GB both times - once again 16MB short.

I have just run Memtest from the current PCW DVD. It gets through all tests without any errors, but it reports 4079GB total memory.

Do I have a problem, or is there something going on that I don't know about?

:) Not poking fun.... But with 16MB missing from 4080GB!!! I wouldn't be worried (LOL).Wish I had enough $$$ to have THAT much memory in my PC! I know it should be 4080MB (4GB)...........

SolMiester
28-06-2011, 01:23 PM
Maybe it's a BIOS bug. I would contact Gigabyte about it, they might release an update to fix the problem.

Yeah, could very well be BIOS bug...what does Windows report for memory OP?

Snorkbox
28-06-2011, 01:24 PM
:) Not poking fun.... But with 16MB missing from 4080GB!!! I wouldn't be worried (LOL).Wish I had enough $$$ to have THAT much memory in my PC! I know it should be 4080MB (4GB)...........


Should be 4 x 1024 = 4096!

Empathy.
28-06-2011, 01:27 PM
Maybe it's just showing your total usable RAM - amount used or reserved? :waughh: Ehh.. I also wouldn't see a *Need* in complaining, unless it starts showing a rediculous amount of memory lost..


(BTW, fail uni student knowledge, just dropping in the opinions)

dugimodo
28-06-2011, 03:11 PM
I have the same board, it has no onboard graphics. I will be interested to see what my memory is reported as when I get home tonight.

Speedy Gonzales
28-06-2011, 03:26 PM
If 4 x 1024 = 4096, whats 4 x 2048 meant to be (if anyone has 8 GB)?? Around 8192, or 8.3?

SolMiester
28-06-2011, 03:35 PM
I have 8Gb at home, but TBH, i have never paid much attention to the BIOS reading of memory, I see 1st digit 8xxx and think all good!

Current BIOS for the gigabyte board is F4, but it makes no mention of memory status errors!

Snorkbox
28-06-2011, 03:36 PM
If 4 x 1024 = 4096, whats 4 x 2048 meant to be (if anyone has 8 GB)?? Around 8192, or 8.3?

It's 8192 exactly!

Jayess64
28-06-2011, 07:41 PM
:) Not poking fun.... But with 16MB missing from 4080GB!!! I wouldn't be worried (LOL).Wish I had enough $$$ to have THAT much memory in my PC! I know it should be 4080MB (4GB)...........

Err, ahem, yes quite. I have trouble typing and using my fingers at the same time.