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GA-8I915P Duo (Pro), BIOS only detects 3 of 4Gb

GA-8I915P Duo (Pro), BIOS only detects 3 of 4Gb
« on: September 28, 2011, 11:08:55 am »
Hi!

I recently bought 4 Gb of RAM (2*2Gb). The modules are: Corsair TWIN2X4096-6400C5C 4GB 800MHz C5 DDR2 Memory Kit

My problem is that the BIOS (updated to F6 version) only detects 3Gb, so my Windows 7 Pro 64 has the same amount of memory (sic).

The BIOS informs that it's working in DUAL Channel Mode (I don't understand how it's possible if one of the modules has 1 Gb not available) and I have tested the 3Gb with memtest without errors.

Could you help me to use all the memory installed or the motherboard has any kind of limitation to use 4Gb?

Thank you very much.

Regards

« Last Edit: September 28, 2011, 11:47:23 am by ManOfSteel »

Aussie Allan

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Re: GA-8I915P Duo (Pro), BIOS only detects 3 of 4Gb
« Reply #1 on: September 28, 2011, 11:29:01 am »

 If you are running 32 bit Operating system..........it will only support 3.2 to 3.6 of the memory installed regardless of how much is installed

 if you are running 64 bit.......test the memory individually with memtest. (Free Download)

  Aussie Allan
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Re: GA-8I915P Duo (Pro), BIOS only detects 3 of 4Gb
« Reply #2 on: September 28, 2011, 11:35:49 am »
But the problem is that the BIOS doesn't detect all the memory in POST  ???

Thank you very much.

Aussie Allan

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Re: GA-8I915P Duo (Pro), BIOS only detects 3 of 4Gb
« Reply #3 on: September 28, 2011, 12:06:20 pm »

   QUOTE:               But the problem is that the BIOS doesn't detect all the memory in POST  Huh!


             Thank you for the extra information.....But to get anywhere......you have to answer questions ..........are you running 32 bit ?

 And two.... test with Memtest with one stick of memory in the number 1 master slot!.....we can start with 5 passes each.....

  Aussie Allan
i7-4790K @4.8GHz 24/7 water clock
MSI XPower AC
32GB corsair  2666Mhz
 GTX-1070Ti full cover
Lange DDC elite pump
G changer360 Rad x2
Phobya 450 balancer
W10 Pro-64
Zigor 2000 UPS
1x500GB for clone
6x2tb- raid5-Storage
C: Evo 970 Pro 512gb
Scratch:Evo 970 Plus 512gb

Dark Mantis

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Re: GA-8I915P Duo (Pro), BIOS only detects 3 of 4Gb
« Reply #4 on: September 28, 2011, 04:15:14 pm »
But the problem is that the BIOS doesn't detect all the memory in POST  ???

Thank you very much.

Hi

I understand your feeling of "does he know what he's talking about" but Allan has reasons for asking a certain question and as he says if you are going to question his way of getting at the answer it will take a long time. Often we ask questions that may not make sense to someone else but do have reasons for asking. It is better just to try and stick to the point if possible. ;)
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Re: GA-8I915P Duo (Pro), BIOS only detects 3 of 4Gb
« Reply #5 on: October 10, 2011, 07:18:24 pm »
Hi!

I tested both modules and one of them was faulty, so I had to ask for a replacement.

I have received the new pair today and I have tested each module individually with Memtest. 5 pass without errors in the master slot each one. Tested together they have passed the test too, but only 3 of the 4 Gb (the problem is still there).

What can I do?

Thank you very much :)

P.D. I run Windows XP SP3 32 bits and Windows 7 Pro 64 bits in dual boot. Both of them only detect 3 Gb.
« Last Edit: October 10, 2011, 07:21:36 pm by ManOfSteel »

Aussie Allan

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Re: GA-8I915P Duo (Pro), BIOS only detects 3 of 4Gb
« Reply #6 on: October 10, 2011, 08:12:44 pm »
 
 Right ........now we have faulty memory out of the fault find ....it's down to BOIS, board or memory compatibility in that order.......(Memory is an outside chance)

 if you have the latest BIOS roll back a version or two.......if you are not running the latest Bios version ....do that in stead.

  If you can possibly help it do not use @Bios .....QFlash will be better ..... remember to NOTKeep Bios data when flashing ..... if you still have the same issue.....odds on you have a crook dimm slot on the board .....or a very , very outside chance of memory that is not compatible with your specific board ...... does it appear on the compatibility list on the memory or mother-board manufactures website ?

  Just out of curiosity.... of the four memory slots......which ones are you populating ?

 

  Aussie Allan
i7-4790K @4.8GHz 24/7 water clock
MSI XPower AC
32GB corsair  2666Mhz
 GTX-1070Ti full cover
Lange DDC elite pump
G changer360 Rad x2
Phobya 450 balancer
W10 Pro-64
Zigor 2000 UPS
1x500GB for clone
6x2tb- raid5-Storage
C: Evo 970 Pro 512gb
Scratch:Evo 970 Plus 512gb

Dark Mantis

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Re: GA-8I915P Duo (Pro), BIOS only detects 3 of 4Gb
« Reply #7 on: October 10, 2011, 08:34:01 pm »
The other thing that is a possibility is bent pins in the CPU socket.

Take all the usual anti-static precautions.

Very carefully remove the heatsink and fan. Probably a slight twisting motion is best to release the two as the thermal paste can act like a glue.

Once off remove the CPU taking extreme care both physically and electrically(static) and place somewhere safe.

Make sure that the lighting is very good and even.

Now scrutinise the socket for any pins that are out of alignment, even slightly.
If in any doubt whatsoever take a couple of macro (close up) photos of the socket and post them on here for us to check.

Also look at the bottom of the CPU at the lands (little copper circles) and make sure that there is a mark in each somewhere near the centre.
If there are any missing marks or any of the pins are obviously bent then that is your problem.

Before refitting the CPU clean off all residue of the old thermal paste and the same on the heatsink and then apply a small amount (about the size of a grain of rice) to the centre of the CPU once it is inserted in the socket.
Gigabyte X58A-UD7
i7 920
Dominators 1600 x6 12GB
6970 2GB
HX850
256GB SSD, Sam 1TB, WDB320GB
Blu-Ray
HAF 932

Gigabyte Z68X-UD5-B3
i7 3770K
Vengeance 1600 16GB
6950 2GB
HCP1200W
Revo Drive x2, 1.5TB WDB RAID0
16x DLRW
StrikeX S7
Full water cooling
3 x 27" Iiy