Had 8gigs of RAM, installed 16gigs more. PC now says "20gigs installed, 12gigs usable". Huh???

Forums › Desktop computing › Had 8gigs of RAM, installed 16gigs more. PC now says "20gigs installed, 12gigs usable". Huh???

dman

953 posts

Ultimate Geek

#150874 6-Aug-2014 12:53

So as my subject says, I took advantage of PB Tech's stock take sale this morning and got some more RAM: Had 8gigs of RAM, installed 16gigs more. PC now says "20gigs installed, 12gigs usable". Huh???

Bit of a mystery to me as to why this is?

My first thought is perhaps my motherboard's drivers are too out of date so it can't handle the extra RAM, but nope, it isn't that (as I've got 1503, and 1801 doesn't change the memory support):
http://support.asus.com/download.aspx?SLanguage=en&m=M5A78L-M/USB3&p=1&s=24&os=30&hashedid=2TinR0vmf3nCJ2GF

Edit: OS is Windows 7 Ultimate.

https://www.youtube.com/c/SoundSpeeding

1 | 2

2120 posts

Uber Geek

#1103240 6-Aug-2014 12:54

What version of Windows?

gzt

17140 posts

Uber Geek

Lifetime subscriber

#1103246 6-Aug-2014 13:05

How much shared memory allocated? It's not the answer but still worth knowing.

dman

953 posts

Ultimate Geek

#1103249 6-Aug-2014 13:07

Oops, stupid me for not mentioning that! It was the first thing I thought about double checking. But yes, I've got Windows 7 Ultimate.

By shared memory, do you mean memory shared with my GPU? Don't think I have any shared with it (?), I have a Radeon 7850 2GB

https://www.youtube.com/c/SoundSpeeding

gzt

17140 posts

Uber Geek

Lifetime subscriber

#1103254 6-Aug-2014 13:11

Latest bios?

Coil

6614 posts

Uber Geek
Inactive user

#1103256 6-Aug-2014 13:11

dman: Oops, stupid me for not mentioning that! It was the first thing I thought about double checking. But yes, I've got Windows 7 Ultimate.

By shared memory, do you mean memory shared with my GPU? Don't think I have any shared with it (?), I have a Radeon 7850 2GB

Run DX Diag and post results here.

gzt

17140 posts

Uber Geek

Lifetime subscriber

#1103257 6-Aug-2014 13:14

gzt: Latest bios?

I see, the 1503 adds memory compatibility. The 1801 does not note that purpose. Personally I would install it anyway at this point if you are confident with these things.

MikeB4

18435 posts

Uber Geek

ID Verified

Trusted

#1103263 6-Aug-2014 13:18

Are you sure you have the Ultimate and not Home Premium 64bit?

Quic Broadband

Move to New Zealand's best fibre broadband service (affiliate link). Free setup code: R587125ERQ6VE. Note that to use Quic Broadband you must be comfortable with configuring your own router.

gzt

17140 posts

Uber Geek

Lifetime subscriber

#1103266 6-Aug-2014 13:22

dman: Had 8gigs of RAM, installed 16gigs more. PC now says "20gigs installed, 12gigs usable".

What does bios say?

dman

953 posts

Ultimate Geek

#1103273 6-Aug-2014 13:29

TimA:
Run DX Diag and post results here.

I got this:
------------------
System Information
------------------
Time of this report: 8/6/2014, 13:26:56
   Operating System: Windows 7 Ultimate 64-bit (6.1, Build 7601) Service Pack 1 (7601.win7sp1_gdr.140303-2144)
           Language: English (Regional Setting: English)
System Manufacturer: System manufacturer
       System Model: System Product Name
               BIOS: BIOS Date: 11/14/12 10:30:51 Ver: 15.03
          Processor: AMD FX(tm)-8350 Eight-Core Processor            (8 CPUs), ~4.0GHz
             Memory: 20480MB RAM
Available OS Memory: 12270MB RAM
          Page File: 3444MB used, 12301MB available
        Windows Dir: C:\Windows
    DirectX Version: DirectX 11
DX Setup Parameters: Not found
   User DPI Setting: Using System DPI
System DPI Setting: 96 DPI (100 percent)
    DWM DPI Scaling: Disabled
     DxDiag Version: 6.01.7601.17514 64bit Unicode

KiwiNZ: Are you sure you have the Ultimate and not Home Premium 64bit?

Am certain :-)

https://www.youtube.com/c/SoundSpeeding

Batman

Mad Scientist
29766 posts

Uber Geek

Trusted

Lifetime subscriber

#1103275 6-Aug-2014 13:30

sounds like a BIOS issue, the BIOS is holding on to some RAM and not releasing it to windows

but umm don't ask me why though!

are you on 64 bit windows 7?

gzt

17140 posts

Uber Geek

Lifetime subscriber

#1103276 6-Aug-2014 13:34

See what http://www.memtest.org/ detects, and any test issues.

sidefx

3712 posts

Uber Geek

Trusted

#1103281 6-Aug-2014 13:40

I'm going to be "that guy" and ask why you need 24 gig of ram? Are you running vms on it?

"I was born not knowing and have had only a little time to change that here and there." | Octopus Energy | Sharesies
- Richard Feynman

timmmay

20581 posts

Uber Geek

Trusted

Lifetime subscriber

#1103359 6-Aug-2014 14:55

What does the motherboard manual say maximum RAM supported is?

Amosnz

567 posts

Ultimate Geek

Lifetime subscriber

#1103421 6-Aug-2014 15:51

Very wierd.

Make sure the new dimms are both installed in either the blue slots or the black slots, not one in each. I'd usually put the largest dimms into the blue slots.

Check in the bios to see if all 4 dimms are detected before windows. (System Information from the front page).
Also check the Memory Speed is set for Auto (Advanced - Jumperfree Configuration - Memory Clock Mode), and perhaps try disabling Channel Interleaving (Advanced - Chipset - DRAM Controller - Channel Interleaving).

Speedtest

Athlonite

1828 posts

Uber Geek
Inactive user

#1103445 6-Aug-2014 16:18

I suggest you read your manual and stick to what the memory QVL for type/sizes of dimms you mobo supports

apparently you mobo currently supports upto 32GB of DDR3-2000MHz ram but the combination you installed maybe leading to only one channel being Usable ie: 1x4GB + 1x8Gb

http://dlcdnet.asus.com/pub/ASUS/mb/SocketAM3+/M5A78L-M_USB3/E8017_M5A78L-M-USB3.pdf

if you have the above setup 1x8GB + 1x4GB in a channel it will automatically remap the memory to the smallest dimms size so 1x8 becomes 1x4GB + 1x4GB

1 | 2