16GB RAM (7.90) usable?

Willir · 16 Apr 2017 at 20:29

I have 3 sticks of red HyperX Fury ram.

2 X 4Gb
1 X 8Gb

Previously had just the 2 4gb sticks to give me the usable amount of memory of 8Gb, no problems. Today I install an 8Gb stick to double memory to 16Gb. My BIOS shows that there are 3 sticks installed, but only 8Gb showing. Also in system it states that there is 16Gb installed but only 7.90Gb usable.

I have tried all slots on the motherboard and also tried setting maximum memory in advanced BOOT options in msconfig.

Does anybody have any idea as to what the problem can be? Specs in signature.

Thanks.

muon · 16 Apr 2017 at 20:33

Why would you do this? Your memory speed will be halved as they can't run in dual channel mode.

Willir · 16 Apr 2017 at 20:47

How do you mean? So HyperX Fury don't run in dual channel mode?

rolypolyman · 16 Apr 2017 at 23:11

Hi according to your motherboard manual it only maps your 2x4gb sticks for dual channel and your 1x8gb stick as single channel and they would have to be in the correct slots, ie the 4gb sticks in slots A1 and B1 or A2 and B2 and the single 8gb in one of the other slots. May have something to do with this.

Willir · 17 Apr 2017 at 12:02

rolypolyman said:
Hi according to your motherboard manual it only maps your 2x4gb sticks for dual channel and your 1x8gb stick as single channel and they would have to be in the correct slots, ie the 4gb sticks in slots A1 and B1 or A2 and B2 and the single 8gb in one of the other slots. May have something to do with this.

Thanks for the advice, but I have tried all slots and still only the 8Gb is usable. If I try the 1 8Gb stick on its own, the machine will not post or boot. The 2 X 4Gb sticks, boot no problem. The 2 X 4Gb sticks & the 1 8Gb stick are recognized but like I said only 8 is usable out of the 16.

Could it be that there is a setting in the BIOS I need to enable in order for the single channel to switch to use dual?

Surely there is a way of the 1 X 8Gb stick being usable, would it be worth getting another 2 X 4Gb sticks to replace the 8Gb?

Woden · 17 Apr 2017 at 12:07

You might need a bios update or the 8gb may be faulty.

Either way 2x4gb would be much better as toy need your RAM in pairs to run dual channel. With single 8GB you're halving your speed.

Willir · 17 Apr 2017 at 12:18

I will try a bios update to see if thats the problem.

Right okay so that explains why the 2 X 4gb sticks run together in dual. I guess by the sounds of it there is no way to have the other 8Gb usable unless I buy another stick of it OR replace with another 2 X 4Gb sticks?

*Edit* The 8Gb stick works fine in my brothers machine so its not faulty.

Quartz · 17 Apr 2017 at 12:21

Exactly which version of Windows 7 are you using? Windows 7 Basic has a limit of 8 GB (as does Windows Home Server 2011).

See here.

Willir · 17 Apr 2017 at 12:23

Quartz said:
Exactly which version of Windows 7 are you using? Windows 7 Basic has a limit of 8 GB (as does Windows Home Server 2011).

See here.

Already considered this, I'm running Windows 7 Pro (64bit) and I understand the limit is 192Gb.

Willir · 17 Apr 2017 at 12:53

Just tried updating BIOS and I already have the latest update, Version 0901.

HoneyBadger · 18 Apr 2017 at 12:39

As a test, take out 1x4GB and replace with the 8GB Stick, does it give you 12GB useable?

Willir · 18 Apr 2017 at 20:18

HoneyBadger said:
As a test, take out 1x4GB and replace with the 8GB Stick, does it give you 12GB useable?

I tried this just before, firstly I tried 1 X 4gb and the 8gb in slots A1 & A2 as you recommended, resulted in no boot or post. I then tried 1 X 4gb in A1 and the 8gb in B1, it booted, shown 12gb, but only 4gb usable.
I know my 8Gb dimm isnt defected or faulty because it works fine in my brothers machine.

TransTechGirl · 18 Apr 2017 at 20:28

Much as I would love to be able to fix your problem I can't think of anything else to try; however, as above I think it is a pointless endeavor and you would be better returning the 8Gb stick and getting two 4Gb sticks so as to get them running in dual channel mode.

Willir · 18 Apr 2017 at 20:46

Yeah I was thinking of just getting another 2 X 4Gb sticks, just a bit odd as to why it wouldn't just work as expected. The one thing I have not tried is to change the frequency speeds, is this recommended to do and if so what speeds should I change them to?

TransTechGirl · 18 Apr 2017 at 21:30

I can't see how changing the speeds would make a difference, if the sticks are different speeds then the MB should just down clock the faster sticks to the speeds of the slowest stick. I assume that the frequency you have bought is supported by your MB?

Willir · 18 Apr 2017 at 21:32

All 3 sticks are 1866Mhz each and yes my ASUS 970 mobo definitely supports them speeds.

Quartz · 18 Apr 2017 at 22:35

TransTechGirl said:
an't see how changing the speeds would make a difference,

It used to be the case - a decade or more ago - that the more sticks of RAM you had, the slower the speed had to be.

Willir · 19 Apr 2017 at 11:39

Quartz said:
It used to be the case - a decade or more ago - that the more sticks of RAM you had, the slower the speed had to be.

I was reading somewhere online that its possible to lower the speeds and it would recognize all 3 sticks as usable. I may try it to test out but got a feeling my best bet is to get another 2 X 4gb sticks.

Quartz · 19 Apr 2017 at 12:13

Rather than having 4x 4 GB sticks I would have 2x 8 GB sticks, as this will allow 4x 8 GB at a later date.

BTW You may find that 2x 4 GB plus 2x 8 GB (for 24 GB total) works just fine.

Willir · 19 Apr 2017 at 12:56

Quartz said:
Rather than having 4x 4 GB sticks I would have 2x 8 GB sticks, as this will allow 4x 8 GB at a later date.

BTW You may find that 2x 4 GB plus 2x 8 GB (for 24 GB total) works just fine.

Right okay, thanks for the heads up, I may go with another 8Gb stick eventually then.