2006-10-26 13:30:47

by Marc Perkel

[permalink] [raw]
Subject: Hardware Problem - Asus A8N-VM CSM

OK - this is a little off topic so I'll apologize and thank you for your
help in advance.

I have 4 Linux servers using the Asus A8N-VM CSM motherboard. They all
have the latest 1001 bios. The all have 4 gigs of ram, and they all have
dual core athlons.

The problem. 2 out of the 4 sees all 4 gigs of ram. The other 2 see only
2.8 gigs of ram. And it's hardware related because in the bios setup the
ones that show 2.8 show it in the bios.

The motherboards were not prchased at the same time. All have different
brands of ram. And the processors are different. The 2 that don't see
all the ram are the newest ones.

I tried swapping ram between one that saw 2.8 gigs and one that saw 4
gigs and the problem stays with the motherboard. I haven't yet swapped
out the processors.

So - I'm a little stumped. Can someone point me in the right direction?


2006-10-26 14:34:24

by Marc Perkel

[permalink] [raw]
Subject: Re: Hardware Problem - Asus A8N-VM CSM



Marc Perkel wrote:
> OK - this is a little off topic so I'll apologize and thank you for
> your help in advance.
>
> I have 4 Linux servers using the Asus A8N-VM CSM motherboard. They all
> have the latest 1001 bios. The all have 4 gigs of ram, and they all
> have dual core athlons.
>
> The problem. 2 out of the 4 sees all 4 gigs of ram. The other 2 see
> only 2.8 gigs of ram. And it's hardware related because in the bios
> setup the ones that show 2.8 show it in the bios.
>
> The motherboards were not prchased at the same time. All have
> different brands of ram. And the processors are different. The 2 that
> don't see all the ram are the newest ones.
>
> I tried swapping ram between one that saw 2.8 gigs and one that saw 4
> gigs and the problem stays with the motherboard. I haven't yet swapped
> out the processors.
>
> So - I'm a little stumped. Can someone point me in the right direction?
>

Answering my own question perhaps. Could it be related to whether or not
the processor is a "revision e" chip?

2006-10-26 16:34:11

by Langsdorf, Mark

[permalink] [raw]
Subject: RE: Hardware Problem - Asus A8N-VM CSM

> > The problem. 2 out of the 4 sees all 4 gigs of ram. The other 2 see
> > only 2.8 gigs of ram. And it's hardware related because in the bios
> > setup the ones that show 2.8 show it in the bios.
> >
> > The motherboards were not prchased at the same time. All have
> > different brands of ram. And the processors are different.
> > The 2 that don't see all the ram are the newest ones.
> >
> > I tried swapping ram between one that saw 2.8 gigs and one
> > that saw 4 gigs and the problem stays with the motherboard.
> > I haven't yet swapped out the processors.
> >
> > So - I'm a little stumped. Can someone point me in the
> > right direction?

Usually, missing memory comes from the PCI I/O hole, or the
IOMMU/AGP/framebuffer overlays. Does your BIOS have an
options for creating a memory hole or hoisting memory? If
so, are the settings between the 4G machines different from
the 2.8G machines?

Also, do you have an IOMMU aperture enabled and if so, how
large?

Are there any hardware differences between the systems, like
different AGP or PCI graphics cards?

> Answering my own question perhaps. Could it be related to
> whether or not the processor is a "revision e" chip?

Possibly, but I'd expect the RevE parts to see more DRAM than
the earlier parts.

-Mark Langsdorf
AMD, Inc.


2006-10-27 16:41:38

by Marc Perkel

[permalink] [raw]
Subject: Re: Hardware Problem - Asus A8N-VM CSM



Langsdorf, Mark wrote:
>>> The problem. 2 out of the 4 sees all 4 gigs of ram. The other 2 see
>>> only 2.8 gigs of ram. And it's hardware related because in the bios
>>> setup the ones that show 2.8 show it in the bios.
>>>
>>> The motherboards were not prchased at the same time. All have
>>> different brands of ram. And the processors are different.
>>> The 2 that don't see all the ram are the newest ones.
>>>
>>> I tried swapping ram between one that saw 2.8 gigs and one
>>> that saw 4 gigs and the problem stays with the motherboard.
>>> I haven't yet swapped out the processors.
>>>
>>> So - I'm a little stumped. Can someone point me in the
>>> right direction?
>>>
>
> Usually, missing memory comes from the PCI I/O hole, or the
> IOMMU/AGP/framebuffer overlays. Does your BIOS have an
> options for creating a memory hole or hoisting memory? If
> so, are the settings between the 4G machines different from
> the 2.8G machines?
>
> Also, do you have an IOMMU aperture enabled and if so, how
> large?
>
> Are there any hardware differences between the systems, like
> different AGP or PCI graphics cards?
>
>
>> Answering my own question perhaps. Could it be related to
>> whether or not the processor is a "revision e" chip?
>>
>
> Possibly, but I'd expect the RevE parts to see more DRAM than
> the earlier parts.
>
>
>

I fixed the problem. It wasn't a Revision E issue after all. I just
pulled the battery and when it came up clean it saw all the memory.
Thanks for your help.

2006-10-28 23:14:42

by Bill Davidsen

[permalink] [raw]
Subject: Re: Hardware Problem - Asus A8N-VM CSM

Marc Perkel wrote:
>
>
> Langsdorf, Mark wrote:
>>>> The problem. 2 out of the 4 sees all 4 gigs of ram. The other 2 see
>>>> only 2.8 gigs of ram. And it's hardware related because in the bios
>>>> setup the ones that show 2.8 show it in the bios.
>>>>
>>>> The motherboards were not prchased at the same time. All have
>>>> different brands of ram. And the processors are different. The 2
>>>> that don't see all the ram are the newest ones.
>>>>
>>>> I tried swapping ram between one that saw 2.8 gigs and one that saw
>>>> 4 gigs and the problem stays with the motherboard.
>>>> I haven't yet swapped out the processors.
>>>>
>>>> So - I'm a little stumped. Can someone point me in the right direction?
>>>>
>>
>> Usually, missing memory comes from the PCI I/O hole, or the
>> IOMMU/AGP/framebuffer overlays. Does your BIOS have an
>> options for creating a memory hole or hoisting memory? If
>> so, are the settings between the 4G machines different from
>> the 2.8G machines?
>>
>> Also, do you have an IOMMU aperture enabled and if so, how
>> large?
>>
>> Are there any hardware differences between the systems, like
>> different AGP or PCI graphics cards?
>>
>>
>>> Answering my own question perhaps. Could it be related to whether or
>>> not the processor is a "revision e" chip?
>>>
>>
>> Possibly, but I'd expect the RevE parts to see more DRAM than
>> the earlier parts.
>>
>>
>>
>
> I fixed the problem. It wasn't a Revision E issue after all. I just
> pulled the battery and when it came up clean it saw all the memory.
> Thanks for your help.
>
Would have been interesting to use the "reset to factory defaults"
option, just to see if some bit isn't set to known state doing that.

--
Bill Davidsen <[email protected]>
Obscure bug of 2004: BASH BUFFER OVERFLOW - if bash is being run by a
normal user and is setuid root, with the "vi" line edit mode selected,
and the character set is "big5," an off-by-one errors occurs during
wildcard (glob) expansion.

2006-10-29 04:05:19

by Marc Perkel

[permalink] [raw]
Subject: Re: Hardware Problem - Asus A8N-VM CSM



Bill Davidsen wrote:
> Marc Perkel wrote:
>>
>>
>> Langsdorf, Mark wrote:
>>>>> The problem. 2 out of the 4 sees all 4 gigs of ram. The other 2
>>>>> see only 2.8 gigs of ram. And it's hardware related because in the
>>>>> bios setup the ones that show 2.8 show it in the bios.
>>>>>
>>>>> The motherboards were not prchased at the same time. All have
>>>>> different brands of ram. And the processors are different. The 2
>>>>> that don't see all the ram are the newest ones.
>>>>>
>>>>> I tried swapping ram between one that saw 2.8 gigs and one that
>>>>> saw 4 gigs and the problem stays with the motherboard.
>>>>> I haven't yet swapped out the processors.
>>>>>
>>>>> So - I'm a little stumped. Can someone point me in the right
>>>>> direction?
>>>>>
>>>
>>> Usually, missing memory comes from the PCI I/O hole, or the
>>> IOMMU/AGP/framebuffer overlays. Does your BIOS have an
>>> options for creating a memory hole or hoisting memory? If
>>> so, are the settings between the 4G machines different from
>>> the 2.8G machines?
>>>
>>> Also, do you have an IOMMU aperture enabled and if so, how
>>> large?
>>>
>>> Are there any hardware differences between the systems, like
>>> different AGP or PCI graphics cards?
>>>
>>>
>>>> Answering my own question perhaps. Could it be related to whether
>>>> or not the processor is a "revision e" chip?
>>>>
>>>
>>> Possibly, but I'd expect the RevE parts to see more DRAM than
>>> the earlier parts.
>>>
>>>
>>>
>>
>> I fixed the problem. It wasn't a Revision E issue after all. I just
>> pulled the battery and when it came up clean it saw all the memory.
>> Thanks for your help.
>>
> Would have been interesting to use the "reset to factory defaults"
> option, just to see if some bit isn't set to known state doing that.
>

Actually that's what it tuened out to be. It had nothing to do with
Revision E.