ASRock.com Homepage
Forum Home Forum Home > Technical Support > AMD Motherboards
  New Posts New Posts RSS Feed - Help Understanding Dual Channel Memory
  FAQ FAQ  Forum Search Search  Events   Register Register  Login Login

Help Understanding Dual Channel Memory
 Post Reply Post Reply Page  12>
Author
Message
  Topic Search Topic Search  Topic Options Topic Options
CliffyK View Drop Down
Groupie
Groupie


Joined: 31 May 2024
Location: Saint Augustine
Status: Offline
Points: 290 		Post Options Post Options   Thanks (0) Thanks(0)   Quote CliffyK Quote  Post ReplyReply Direct Link To This Post Topic: Help Understanding Dual Channel Memory
    Posted: 31 May 2024 at 9:06am
Hello all, new member here.

I just replaced an old Asus M5A78L-M_LX mobo in my 15 y.o. home-built workstation with an ASRock 970m Pro3--I re-used my AMD FX-8350 CPU. Video is handled by a GEForce GT-740

I installed four (4) new 8 GB DDR3 1600MHz RAM modules thinking this would provide 32 GB for my primary boot Linux Mint 21.3 system, however I find that while Linux sees all 4 modules (acknowledging 32 GB "on the mobo") only 16 GB is "available" to the o/s?

The mobo BIOS sees all four 8GB "sticks", I have shuffled them about in the slots with no change?

Booting to Win 10 (dual boot setup) revealed Windows had the same perspective; 32 GB installed, 16 GB "available"?

I also did a new installation of Mint 21.3 to another drive (same machine) and found it too only recognized 16 GB "available" memory

Is this a "dual-channel" memory issue? Would two (2) 16 GB modules in slots A-1 and B-1 (or A-2 and B-2) provide the 32 GB available to the o/s that I seek?

TIA,

-cliff-

BTW, the new mobo booted right up with no other issues!
    
Our most basic common link is that we all inhabit this planet.
We all breathe the same air. We all cherish our children's future.
And we are all mortal.

-John F. Kennedy-
Back to Top
CliffyK View Drop Down
Groupie
Groupie


Joined: 31 May 2024
Location: Saint Augustine
Status: Offline
Points: 290 		Post Options Post Options   Thanks (0) Thanks(0)   Quote CliffyK Quote  Post ReplyReply Direct Link To This Post Posted: 31 May 2024 at 12:09pm
Additional info:

I pulled the memory from slots A-2 and B-2, leaving A-1 and B-1 both populated with 8 GB sticks. BIOS saw both, but indicated "Single Channel Mode".

Linux and Win10 both reported 16 GB installed but only 8 GB available to the o/s? Put in all four sticks and was back to where I was (32 GB installed, 16 GB available to the o/s); BIOS still says "Single Channel Mode", with all four slots loaded--is the mobo bad?

IF I get ambitious I will try slots A-2/B-2 loaded and just A-1/B-1 loaded...
Our most basic common link is that we all inhabit this planet.
We all breathe the same air. We all cherish our children's future.
And we are all mortal.

-John F. Kennedy-
Back to Top
Xaltar View Drop Down
Moderator Group
Moderator Group
Avatar

Joined: 16 May 2015
Location: Europe
Status: Offline
Points: 24398 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Xaltar Quote  Post ReplyReply Direct Link To This Post Posted: 02 Jun 2024 at 7:04am
Try each stick on it's own, typically that issue happens when you have a bad module.
Back to Top
CliffyK View Drop Down
Groupie
Groupie


Joined: 31 May 2024
Location: Saint Augustine
Status: Offline
Points: 290 		Post Options Post Options   Thanks (0) Thanks(0)   Quote CliffyK Quote  Post ReplyReply Direct Link To This Post Posted: 02 Jun 2024 at 7:26am
Thank you for your reply! After trying every possible combination of modules (including "one-at-a-time", I'm pretty sure I have found the problem, am going to wait 'til I'm 100% sure to followup.

After the great memory swap I pulled the CPU and found it was missing a pin on the outer row 45° "opposite" the "triangle"--looking at my old mobo I found the pin stuck in the socket where it had been living happily for 12 years prior to my disturbing it. Odd that the CPU almost fell out when I removed it and that it would be a pin that did not disable the CPU entirely--it works fine other than no dual-channel memory mode.

Got a "new-to-me" CPU from a trusted vendor on eBay coming in on Tuesday, hopefully that will solve the mystery.

I will come back here and mark the post as Solved if I'm good.

Again thank you for your reply!

-cliff-
Our most basic common link is that we all inhabit this planet.
We all breathe the same air. We all cherish our children's future.
And we are all mortal.

-John F. Kennedy-
Back to Top
Xaltar View Drop Down
Moderator Group
Moderator Group
Avatar

Joined: 16 May 2015
Location: Europe
Status: Offline
Points: 24398 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Xaltar Quote  Post ReplyReply Direct Link To This Post Posted: 02 Jun 2024 at 7:38am
That would do it for sure. Sometimes you can get away with a missing pin, not all
are used for anything critical but more often than not, it causes issues.
Back to Top
CliffyK View Drop Down
Groupie
Groupie


Joined: 31 May 2024
Location: Saint Augustine
Status: Offline
Points: 290 		Post Options Post Options   Thanks (0) Thanks(0)   Quote CliffyK Quote  Post ReplyReply Direct Link To This Post Posted: 02 Jun 2024 at 9:26am
I have tried to find a "pin-out" diagram for the AMD3+ socket, with no luck--I did find there are 938 pins, so it was pretty close to a "1 in a 1000" chance I'd get the dual-channel pin...
Our most basic common link is that we all inhabit this planet.
We all breathe the same air. We all cherish our children's future.
And we are all mortal.

-John F. Kennedy-
Back to Top
CliffyK View Drop Down
Groupie
Groupie


Joined: 31 May 2024
Location: Saint Augustine
Status: Offline
Points: 290 		Post Options Post Options   Thanks (0) Thanks(0)   Quote CliffyK Quote  Post ReplyReply Direct Link To This Post Posted: 02 Jun 2024 at 9:33am
I found an AMD3 pin-out, on that socket it's a "Memory Channel B" clock signal--so that makes sense...
Our most basic common link is that we all inhabit this planet.
We all breathe the same air. We all cherish our children's future.
And we are all mortal.

-John F. Kennedy-
Back to Top
CliffyK View Drop Down
Groupie
Groupie


Joined: 31 May 2024
Location: Saint Augustine
Status: Offline
Points: 290 		Post Options Post Options   Thanks (0) Thanks(0)   Quote CliffyK Quote  Post ReplyReply Direct Link To This Post Posted: 06 Jun 2024 at 10:01pm
Well, I got the "new-to-me" CPU from eBay--DOA, missing two pins; good vendor though, sent it back for refund...

Got another on order, again coming in on Tuesday--I will be sure to report back with an update...
Our most basic common link is that we all inhabit this planet.
We all breathe the same air. We all cherish our children's future.
And we are all mortal.

-John F. Kennedy-
Back to Top
Xaltar View Drop Down
Moderator Group
Moderator Group
Avatar

Joined: 16 May 2015
Location: Europe
Status: Offline
Points: 24398 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Xaltar Quote  Post ReplyReply Direct Link To This Post Posted: 06 Jun 2024 at 10:50pm
You can check youtube for pin repair tutorials/videos if you like, a fun little
side project given the CPU is basically useless anyway.
Back to Top
CliffyK View Drop Down
Groupie
Groupie


Joined: 31 May 2024
Location: Saint Augustine
Status: Offline
Points: 290 		Post Options Post Options   Thanks (1) Thanks(1)   Quote CliffyK Quote  Post ReplyReply Direct Link To This Post Posted: 07 Jun 2024 at 12:19am
Thank you for the suggestion, however I have Parkinson's making my replacing a CPU pin unlikely to succeed...
Our most basic common link is that we all inhabit this planet.
We all breathe the same air. We all cherish our children's future.
And we are all mortal.

-John F. Kennedy-
Back to Top
 Post Reply Post Reply Page  12>
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.04
Copyright ©2001-2021 Web Wiz Ltd.

This page was generated in 0.109 seconds.