Single Channel Problem

[Kenshin13]

I have Samsung Np355V5C-s0btr laptop 8 gb (2X4) ram but I can use 3.46 gb only (4.54 gb seems hardware reserved)
Bios Can see 8 gb Ram but
memstest can see 3.98mb only
I have 2 slots only and bios dont have advanced settings or memory settings
my memory stciks are same (I didnt change orginal memory sticks or add new memory sticks)
computer is running at single mode
OS: Windows 7 64 bit
Bios Version AmiBios P70ABF (Latest Version)
How Can I activate Double Channel mode?
Sorry For Bad Eng
Regards

 

[Darkbreeze]

Your laptop may be limited to 4GB and some of it is likely reserved for system hardware. It sounds more like a 32 bit windows issue but you say you have 64 bit installed. I'll check your specs.

 

[Darkbreeze]

It seems it does support 8GB. Are both modules identical or did you add a 4GB module that is different from the other stick?

If so, what are the model numbers of both sticks.

 

[Kenshin13]

laptop support max 8 gb ram Im sure it was working with 8 gb(7.86 gb usable)
I didnt touch orginal memory sticks and I tried reset CMOS, reinstall windows and replace ram sticks but still same
I got that report from CPU-Z
"
Memory SPD
DIMM # 1
SMBus address 0x50
Memory type DDR3
Module format SO-DIMM
Manufacturer (ID) Samsung (CE000000000000000000)
Size 4096 MBytes
Max bandwidth PC3-12800 (800 MHz)
Part number M471B5273EB0-CK0
Serial number 351CDB42
Manufacturing date Week 49/Year 12
Number of banks 8
Nominal Voltage 1.50 Volts
EPP no
XMP no
AMP no
JEDEC timings table CL-tRCD-tRP-tRAS-tRC @ frequency
JEDEC #1 5.0-5-5-14-19 @ 380 MHz
JEDEC #2 6.0-6-6-16-22 @ 457 MHz
JEDEC #3 7.0-7-7-19-26 @ 533 MHz
JEDEC #4 8.0-8-8-22-30 @ 609 MHz
JEDEC #5 9.0-9-9-24-33 @ 685 MHz
JEDEC #6 10.0-10-10-27-37 @ 761 MHz
JEDEC #7 11.0-11-11-28-39 @ 800 MHz

DIMM # 2
SMBus address 0x51
Memory type DDR3
Module format SO-DIMM
Manufacturer (ID) Samsung (CE000000000000000000)
Size 4096 MBytes
Max bandwidth PC3-12800 (800 MHz)
Part number M471B5273EB0-CK0
Serial number 97A55B95
Manufacturing date Week 49/Year 12
Number of banks 8
Nominal Voltage 1.50 Volts
EPP no
XMP no
AMP no
JEDEC timings table CL-tRCD-tRP-tRAS-tRC @ frequency
JEDEC #1 5.0-5-5-14-19 @ 380 MHz
JEDEC #2 6.0-6-6-16-22 @ 457 MHz
JEDEC #3 7.0-7-7-19-26 @ 533 MHz
JEDEC #4 8.0-8-8-22-30 @ 609 MHz
JEDEC #5 9.0-9-9-24-33 @ 685 MHz
JEDEC #6 10.0-10-10-27-37 @ 761 MHz
JEDEC #7 11.0-11-11-28-39 @ 800 MHz
"

 

[Darkbreeze]

If possible, please go to control panel, system, and take a screenshot of the main system information window. Post the screenshot here using a generated link from an image hosting site like www.tinypic.com or similar online service.

How to post screenshots on Tom's Hardware forums: http://www.tomshardware.com/answers/id-2173703/post-images-tomshardware-guide.html

It should look like this:

 

[Kenshin13]

If possible, please go to control panel, system, and take a screenshot of the main system information window. Post the screenshot here using a generated link from an image hosting site like www.tinypic.com or similar online service.

How to post screenshots on Tom's Hardware forums: http://www.tomshardware.com/answers/id-2173703/post-images-tomshardware-guide.html

It should look like this:

sure its my system

and cpu-z capture

 

[Darkbreeze]

Several things I would try.

First, go into the BIOS and press whatever function key is necessary to reset the BIOS to optimal or default settings, save settings and reboot.

If that doesn't work, click the start on the desktop, type msconfig into the run or search box and enter, in the system configuration window that opens click the boot tab. Click advanced options and check (Or uncheck) the box next to Max RAM. Save settings and reboot. If that doesn't correct the problem you can go back in there and change it back.

Go into the Programs and features section of control panel and made sure there are no RAM disk applications installed. If there are, you'll need to uninstall the application but if there are programs that have their cache designated on the RAM disk it might cause issues so you'll need to change those settings for any application using the RAMdisk including possibly internet explorer and the windows system temp file. If there is a RAMdisk application installed let me know and I'll tell you how to check for and change those settings.

Try switching places with the RAM modules that are installed. Make sure they are fully seated as well.

 

[Kenshin13]

I did already msconfig fix,replace mem sticks,reinstall differ win version,update bios and reset bios to default settings but still same

I booted system with kalilinux it see 3.8 gb such as memtest (dont see 8 gb) maybe my one slot fault bcs system doest run double ram mode
little addition I tested my mem sticks an another computer its worked good

 

[Darkbreeze]

Dual channel operation has little to do with the availability of the memory or lack of availability. IF there was a dual channel issue, it would simply run in single channel operation. Dual channel requires identical modules, or at least modules with very similar specs.

Can you take a screenshot of CPU-Z SPD tab. One screenshot for each module. You'll need to change the slot number in the drop down box to get the info for each module.

 

[Kenshin13]

slot 1

slot 2

 

[Darkbreeze]

I've contacted one of the moderators here who is about the most knowledgeable with memory I know of that might be able to help. I'm about out of ideas.

Being as those ARE identical modules, but are not running in dual channel, it might be that it IS related, despite my earlier misgivings.

 

[Tradesman1]

Have you tried cleaning the DRAM contacts and reseating the Sticks? Might also try reflashing BIOS or contacting the manufacturer, most all laptops have locked BIOSs and not a whole lot you can do unlike a desktop

 

[Darkbreeze]

Run GPU-Z and see if tells you how much system memory is allocated to the GPU.

 

[Kenshin13]

Have you tried cleaning the DRAM contacts and reseating the Sticks? Might also try reflashing BIOS or contacting the manufacturer, most all laptops have locked BIOSs and not a whole lot you can do unlike a desktop

yes I did I gave laptop to a technical service for fix they changed mem slots but still same
so Can I unlock Advanced Bios settings is that possible? for see memory settings

 

[Kenshin13]

Run GPU-Z and see if tells you how much system memory is allocated to the GPU.

7670m already have unshared 2gb mem maybe 128mb shared

 

[Darkbreeze]

IF you're running in dual graphics mode, which it looks like you are, then it's anybody's guess how much memory is actually being used by the graphics. It would seem to be 2GB, which is clearly more, by far, than what you are unable to access due to hardware reservation. It might be that the 2GB is only what is actually being use and that 4GB or thereabouts are being reserved for it. Again, that's just a guess as I don't have a ton of experience with dual graphics configurations on laptops, but it seems at least possible. You might try disabling the onboard graphics in the BIOS and only allowing the PCI graphics to be enabled.

 

[Kenshin13]

IF you're running in dual graphics mode, which it looks like you are, then it's anybody's guess how much memory is actually being used by the graphics. It would seem to be 2GB, which is clearly more, by far, than what you are unable to access due to hardware reservation. It might be that the 2GB is only what is actually being use and that 4GB or thereabouts are being reserved for it. Again, that's just a guess as I don't have a ton of experience with dual graphics configurations on laptops, but it seems at least possible. You might try disabling the onboard graphics in the BIOS and only allowing the PCI graphics to be enabled.

I dont have advanced settings in BIOS so Can I install one module 8gb memory stick? if that possible wanna run 8 gb ram at single mode
thanks.

 

[Darkbreeze]

I don't think that's possible. I can't find much information about that model, since it's a model foreign to the US market and the regional Samsung website for that model doesn't offer much if any useful information, but the Np355V5C (Non-S0btr models) US models all show support only for 4GB modules.

I think it's likely you have a bad module.

 

[Kenshin13]

I don't think that's possible. I can't find much information about that model, since it's a model foreign to the US market and the regional Samsung website for that model doesn't offer much if any useful information, but the Np355V5C (Non-S0btr models) US models all show support only for 4GB modules.

I think it's likely you have a bad module.

ok Thanks for replies

 

[Darkbreeze]

Sorry we couldn't get a definitive answer. You can try using a single module, try one, then the other, in each slot, and see what's reported. Maybe it's a failure on the dram slot of the board rather than the memory itself.