Why is my bios showing 4gb instead of 8gb?

[daboto]

Hi
Anyone knows the answer to this?
My Asus Crosshair IV bio is showing 4gb instead of 8gb. I have two sticks and tested both and both shows 4gb instead of 8gb. Also when I add those two sticks it read 8gb (4gb each sticks).

Here are by hardware system.
Asus Crosshair IV
AMD Phenom II 6core 1090T at default 3.20ghz
Got 2 memory sticks that are Corsair DDR3 1666
850w power supply.
And system is running Windows 7 64bit

People said it might be the operating system but as you can see I got 64bit installed.
My ram power in bios is set to 1.5 as mention in asus manual.

Now I ran out of clues on what to do now.
Anyone if you know about this please help me?

Thanks

 

[Sleepingforest]

Make sure your sticks are seated in the correct slots.

 

[Ketchup]

So the BIOS is showing you 8 but Windows is showing 4? The title says the BIOS shows 4, but this line says the BIOS sees 8:

Also when I add those two sticks it read 8gb (4gb each sticks).

 

[daboto]

Make sure your sticks are seated in the correct slots.

I tested all 4 slots. And manual said I can put in either one.

 

[daboto]

So the BIOS is showing you 8 but Windows is showing 4? The title says the BIOS shows 4, but this line says the BIOS sees 8:

BIOS and windows shows 8gb if I added 2 sticks.
My memory sticks are 8gb each so BIOS suppose to show 16gb total but is not.

 

[Ketchup]

BIOS and windows shows 8gb if I added 2 sticks.
My memory sticks are 8gb each so BIOS suppose to show 16gb total but is not.

OK, gotcha. So if you go into Windows and run CPU-Z, does it only show you have one stick?

Are you running the latest BIOS?

 

[daboto]

Yes it's 3029.

 

[Kenmitch]

Welcome to the forum

Your MB doesn't like 8gb memory modules. It's possible you might find a set that will work tho.

General rule of thumb: max memory divided by available slots = max module size.(more often than not)

 

[Mir96TA]

Bios ver ?
Plus Memory Vendor Part No.
According to QVL 12 GB is Max
However Manual says 16 GB MAX not sure what configuration it requires

 

[daboto]

Bios ver ?
Plus Memory Vendor Part No.

It's 3029. I had also reverse it to 3027.

 

[Mir96TA]

Did you try Bios Version 2101

It think Max Single of Memory module is 4 GB or at least that is what QVL saying

 

[Bubbaleone]

Hi
Anyone knows the answer to this?
My Asus Crosshair IV bio is showing 4gb instead of 8gb. I have two sticks and tested both and both shows 4gb instead of 8gb. Also when I add those two sticks it read 8gb (4gb each sticks).

Here are by hardware system.
Asus Crosshair IV
AMD Phenom II 6core 1090T at default 3.20ghz
Got 2 memory sticks that are Corsair DDR3 1666
850w power supply.
And system is running Windows 7 64bit

People said it might be the operating system but as you can see I got 64bit installed.
My ram power in bios is set to 1.5 as mention in asus manual.

Now I ran out of clues on what to do now.
Anyone if you know about this please help me?

Thanks

The Crosshair supports a maximum of 16 GB (4x4 GB) of memory in dual-channel configuration. Per the user manual and memory QVL; your mobo will only support 4 GB DIMMs, which is why it's reporting only half the capacity of the 8 GB DIMMs you're trying to use. 8 GB DIMMs are intended for mobos with four 240-pin DIMM slots that are designed to support a maximum of 32 GB (4x8 GB) of memory.


.

 

[daboto]

Your right Babbaleone, As I see it here at Asus website:
https://www.asus.com/Motherboards/CROSSHAIR_IV_FORMULA/#specifications


Damn it I purchase this motherboard for over $250 when it first release.
But if I only add one stick (8gb). Shouldn't read 8gb? Or does it not matter?

 

[Mir96TA]

Did you try Bios Version 2101

It think Max Single of Memory module is 4 GB or at least that is what QVL saying

Your right Babbaleone, As I see it here at Asus website:


Damn it I purchase this motherboard for over $250 when it first release.
But if I only add one stick (8gb). Shouldn't read 8gb? Or does it not matter?

4 GB is a single Max

 

[VirtualLarry]

I'm a little confused with the prognosis. Isn't the memory controller on-die on AM3 CPUs? So shouldn't the DIMM-size limitations lie with the CPU, not the chipset or motherboard?

Or did they cheap out on those motherboards and not run the additional traces that would have been needed to support 8GB DIMMs?

I think he got sold some wrong DIMMs, not that the mobo can't handle them.

 

[Mir96TA]

I'm a little confused with the prognosis. Isn't the memory controller on-die on AM3 CPUs? So shouldn't the DIMM-size limitations lie with the CPU, not the chipset or motherboard?

Or did they cheap out on those motherboards and not run the additional traces that would have been needed to support 8GB DIMMs?

I think he got sold some wrong DIMMs, not that the mobo can't handle them.

Bios Limitions

 

[Kenmitch]

I'm a little confused with the prognosis. Isn't the memory controller on-die on AM3 CPUs? So shouldn't the DIMM-size limitations lie with the CPU, not the chipset or motherboard?

Or did they cheap out on those motherboards and not run the additional traces that would have been needed to support 8GB DIMMs?

I think he got sold some wrong DIMMs, not that the mobo can't handle them.

The motherboard was released around April of 2010 it looks like. At that time a 8gb stick would have been on the bleeding edge of technology and commanded a HUGE price premium. Think server memory for the 8gb sticks back in 2010.

 

[Mir96TA]

The motherboard was released around April of 2010 it looks like. At that time a 8gb stick would have been on the bleeding edge of technology and commanded a HUGE price premium. Think server memory for the 8gb sticks back in 2010.

Well with that argument.......
Last Bios Update came in Nov 2012; where they could have done the updates.

 

[Soulkeeper]

I had some memory where the heatspreaders had shifted causing contact with the dimm slot and the memory not to seat all the way.
They looked and felt seated, but they weren't and I was only getting half the mem detected.

Also recently I had a hair in a pcie slot causing a card to work at 1x instead of 16x.

 

[daboto]

In the manual on page 2-17 it has a bunch of memory listings (QVL) and it showed my Corshair 8gb memory. And to set it I must set the voltage to 1.65 and timing to 9-9-9-24.
It also said that if I want over 4gb I must set my operating system as 64bit which I have now.
Anyone with the same cpu configuration as mine and has over 16gb of memory please tell me how you done it?

 

[Railgun]

Nowhere does it show a single 8GB module is supported. The OS has nothing to do with module density support. A 4GB module is as large as you can use. It may show your memory but I think you're reading total. You need to look at the rest of the line. Eg 2x4GB which is two sticks of 4GB.

 

[Bubbaleone]

Page 2-17 shows two listings for 8GB of Corsair memory. Both configurations are 4x2GB; 2GB+2GB+2GB+2GB = 8GB. 8GB DIMMs are not supported by your mobo.

.

 

[nenforcer]

http://www.crucial.com/store/listpar...ormula&Cat=RAM

This is also confirmed by the Crucial Memory Advisor

4 x 4GB = 16 GB Maximum Configuration

You can't use 2 x 8GB DIMMS.

 

[rolli59]

I am surprised it reads and runs 8GB stick as 4GB. If the ram is not supported it should not run.

 

[tcsenter]

I'm a little confused with the prognosis. Isn't the memory controller on-die on AM3 CPUs? So shouldn't the DIMM-size limitations lie with the CPU, not the chipset or motherboard?

It's definitely a marketing/support limit imposed by ASUS (in the specs and maybe in the BIOS itself), probably to limit the problems and support requests that ASUS would need to field due to people trying to overclock large capacity DIMMs or 32GB total.

The Phenom II supports 8GB DIMMs up to at least 32GB total across four DIMM slots, so its not a hardware limit.