VA503+: maximum installable memory? DIMM size limitation?

I'm just wondering, can the 504+ handle more than 256MB of memory? Every
time I've tried (with one 256MB stick and assorted other sticks of PC100 and
PC133 flavors and sizes), the system boots but will not run through memtest
without erroring out. If I run the sticks by themselves memtest runs fine.
Will the 503+ work w/256MB PC100 DIMMs? I've noticed the Tyan s1590 (also
based on the VIA MVp3 chipset) doesn't recommend any DIMMs over 128MB in
size. Is this also true of the 503+? All my 503+ manual states about 256MB
DIMMs is that none were available for testing.

--
there is no .sig

The VA-503+ can handle up to 768 MB RAM, consisting of 3 256 MB DIMMs.
The MVP3 chipset can handle a memory density of up to 16 MB per memory
chip. That would mean a 256 MB DIMM must consist of 16 memory chips,
each one containing 16 MB. The 256 MB DIMMs that are more common these
days usually consist of only 8 chips, which will not work because they
consist of 32 MB chips. (In the case of ECC RAM, one extra chip per
side is allowed for the ECC function, so a 256 MB ECC DIMM would have a
total of 18 chips).

Other chipsets from this time period also have the same size
limitations. For example, the Intel 440BX. When these chipsets first
came out, they were designed to handle up to 16 MB/chip, but only 8 MB
chips were available at the time. When the 16 MB chips started coming
out, they worked fine in most of these boards, but some required BIOS
updates to sort out compatability problems.

As for your problems getting the DIMMs to run together, this is often a
result of more memory modules placing more burden on the memory
controller. I do not recall the particulars of the VA-503+ off the top
of my head, but here are some general tips:

Loosen memory timings in BIOS. Set CAS Latency to the highest number,
which would be 3. Also, set the Memory Timings (I forgot the exact
name) more towards "Slow" and away from "Turbo".

If the VA-503+ gives you a way to adjust the memory voltage or I/O
voltage, try bumping it up a notch. The normal DIMM voltage for regular
SDRAM is 3.3 V. Try bumping it up to 3.4 V.

While you are at it, you may check for any BIOS updates in case any
memory issues have been addressed.

By the way, you may hear that the MVP chipset has a maximum *cacheable*
memory size of 255 or 256 MB. Basically, what this means is that if you
put more memory than this in your computer, the overall performance will
actually go down. In practical terms, this means that unless you
actually need more physical RAM than 256 MB, you are better off staying
with 256 MB. On the other hand, if you regular need more than 256 MB,
then you will still benefit from the added RAM, because the it is still
way faster than having your computer access the swapfile on your hard drive.

I hope this helps.

--Alex




Doug wrote:
> I'm just wondering, can the 504+ handle more than 256MB of memory? Every
> time I've tried (with one 256MB stick and assorted other sticks of PC100 and
> PC133 flavors and sizes), the system boots but will not run through memtest
> without erroring out. If I run the sticks by themselves memtest runs fine.
> Will the 503+ work w/256MB PC100 DIMMs? I've noticed the Tyan s1590 (also
> based on the VIA MVp3 chipset) doesn't recommend any DIMMs over 128MB in
> size. Is this also true of the 503+? All my 503+ manual states about 256MB
> DIMMs is that none were available for testing.
>

Well, that cuts it. I guess I'll just stick with 256MB then. It's
interesting that the manual for the Tyan s1590 (also
based on the VIA MVp3 chipset) didn't mention the 256MB limit for cacheable
memory. I never knew about the 16MB per memory chip limitation. Thanks.

--
there is no .sig
"Alex Zorrilla" <> wrote in message
news:...
> The VA-503+ can handle up to 768 MB RAM, consisting of 3 256 MB DIMMs. The
> MVP3 chipset can handle a memory density of up to 16 MB per memory chip.
> That would mean a 256 MB DIMM must consist of 16 memory chips, each one
> containing 16 MB. The 256 MB DIMMs that are more common these days
> usually consist of only 8 chips, which will not work because they consist
> of 32 MB chips. (In the case of ECC RAM, one extra chip per side is
> allowed for the ECC function, so a 256 MB ECC DIMM would have a total of
> 18 chips).
>
> Other chipsets from this time period also have the same size limitations.
> For example, the Intel 440BX. When these chipsets first came out, they
> were designed to handle up to 16 MB/chip, but only 8 MB chips were
> available at the time. When the 16 MB chips started coming out, they
> worked fine in most of these boards, but some required BIOS updates to
> sort out compatability problems.
>
> As for your problems getting the DIMMs to run together, this is often a
> result of more memory modules placing more burden on the memory
> controller. I do not recall the particulars of the VA-503+ off the top of
> my head, but here are some general tips:
>
> Loosen memory timings in BIOS. Set CAS Latency to the highest number,
> which would be 3. Also, set the Memory Timings (I forgot the exact name)
> more towards "Slow" and away from "Turbo".
>
> If the VA-503+ gives you a way to adjust the memory voltage or I/O
> voltage, try bumping it up a notch. The normal DIMM voltage for regular
> SDRAM is 3.3 V. Try bumping it up to 3.4 V.
>
> While you are at it, you may check for any BIOS updates in case any memory
> issues have been addressed.
>
> By the way, you may hear that the MVP chipset has a maximum *cacheable*
> memory size of 255 or 256 MB. Basically, what this means is that if you
> put more memory than this in your computer, the overall performance will
> actually go down. In practical terms, this means that unless you actually
> need more physical RAM than 256 MB, you are better off staying with 256
> MB. On the other hand, if you regular need more than 256 MB, then you
> will still benefit from the added RAM, because the it is still way faster
> than having your computer access the swapfile on your hard drive.
>
> I hope this helps.
>
> --Alex
>
>
>
>
> Doug wrote:
>> I'm just wondering, can the 504+ handle more than 256MB of memory? Every
>> time I've tried (with one 256MB stick and assorted other sticks of PC100
>> and PC133 flavors and sizes), the system boots but will not run through
>> memtest without erroring out. If I run the sticks by themselves memtest
>> runs fine. Will the 503+ work w/256MB PC100 DIMMs? I've noticed the Tyan
>> s1590 (also based on the VIA MVp3 chipset) doesn't recommend any DIMMs
>> over 128MB in size. Is this also true of the 503+? All my 503+ manual
>> states about 256MB DIMMs is that none were available for testing.
>>

On Tue, 15 Nov 2005, Alex Zorrilla typed this :
>The VA-503+ can handle up to 768 MB RAM, consisting of 3 256 MB DIMMs.
>The MVP3 chipset can handle a memory density of up to 16 MB per memory
>chip.
(snip)

Does this apply to the PA-2013 as well?
I suspect it does, as I always regarded the 2013 as the ATX version of
the 503+, but it would be handy to know for sure before I get hold of
one (to replace my much loved and melted 503+).
--
Roger Hunt

Yup, sure does. Same thing goes for the VA-503A, and just about any
other MVP3 chipset motherboard.



Roger Hunt wrote:
> On Tue, 15 Nov 2005, Alex Zorrilla typed this :
>
>>The VA-503+ can handle up to 768 MB RAM, consisting of 3 256 MB DIMMs.
>>The MVP3 chipset can handle a memory density of up to 16 MB per memory
>>chip.
>
> (snip)
>
> Does this apply to the PA-2013 as well?
> I suspect it does, as I always regarded the 2013 as the ATX version of
> the 503+, but it would be handy to know for sure before I get hold of
> one (to replace my much loved and melted 503+).

On Thu, 17 Nov 2005, Alex Zorrilla typed this :
>Yup, sure does. Same thing goes for the VA-503A, and just about any
>other MVP3 chipset motherboard.
>
Thanks. I'm looking forward to firing up this here K6-2+/500 - should be
good for 10-15% overclock. And I'm also going to play with an ancient
(ISA card) Trojan Light Pen, and Win3.1.
>
>Roger Hunt wrote:
>> On Tue, 15 Nov 2005, Alex Zorrilla typed this :
>>
>>>The VA-503+ can handle up to 768 MB RAM, consisting of 3 256 MB DIMMs.
>>>The MVP3 chipset can handle a memory density of up to 16 MB per memory
>>>chip.
>>
>> (snip)
>>
>> Does this apply to the PA-2013 as well?
>> I suspect it does, as I always regarded the 2013 as the ATX version of
>> the 503+, but it would be handy to know for sure before I get hold of
>> one (to replace my much loved and melted 503+).

--
Roger Hunt

My 503+ only has 2 DIMM slots, so the max memory would be 512M. I can
confirm from recent experience that a 256M stick with 8 chips doesn't work
(actually it does, as a 128M stick). To achieve long term (error-free 24
hour memtest) I set DRAM timing to "Normal" and CAS to "3". Trying to run
with faster settings usually failed with single bit errors on test #6 with a
ones-heavy test pattern. My 503+ is offline at present as I'm using the KVM
with a neighbor's sick IBM Netvista. I'll verify my exact settings over the
weekend and report back.

"Alex Zorrilla" <> wrote in message
news:...
> Yup, sure does. Same thing goes for the VA-503A, and just about any
> other MVP3 chipset motherboard.
>
>
>
> Roger Hunt wrote:
> > On Tue, 15 Nov 2005, Alex Zorrilla typed this :
> >
> >>The VA-503+ can handle up to 768 MB RAM, consisting of 3 256 MB DIMMs.
> >>The MVP3 chipset can handle a memory density of up to 16 MB per memory
> >>chip.
> >
> > (snip)
> >
> > Does this apply to the PA-2013 as well?
> > I suspect it does, as I always regarded the 2013 as the ATX version of
> > the 503+, but it would be handy to know for sure before I get hold of
> > one (to replace my much loved and melted 503+).

I double-checked my chipset settings and it appears that the only thing my
system is sensitive to is the CAS value - I need it to be 3. I've used both
"turbo" and "Fast" DRAM timing without problems as long as CAS is 3.
Setting DRAM timing to "Normal" and CAS to 2 causes random single-bit errors
in a 24 hour memtest run.

"J. Michael Milner" <> wrote in message
news:3Ldff.120883$...
> My 503+ only has 2 DIMM slots, so the max memory would be 512M. I can
> confirm from recent experience that a 256M stick with 8 chips doesn't work
> (actually it does, as a 128M stick). To achieve long term (error-free 24
> hour memtest) I set DRAM timing to "Normal" and CAS to "3". Trying to run
> with faster settings usually failed with single bit errors on test #6 with
a
> ones-heavy test pattern. My 503+ is offline at present as I'm using the
KVM
> with a neighbor's sick IBM Netvista. I'll verify my exact settings over
the
> weekend and report back.
>
> "Alex Zorrilla" <> wrote in message
> news:...
> > Yup, sure does. Same thing goes for the VA-503A, and just about any
> > other MVP3 chipset motherboard.
> >
> >
> >
> > Roger Hunt wrote:
> > > On Tue, 15 Nov 2005, Alex Zorrilla typed this :
> > >
> > >>The VA-503+ can handle up to 768 MB RAM, consisting of 3 256 MB DIMMs.
> > >>The MVP3 chipset can handle a memory density of up to 16 MB per memory
> > >>chip.
> > >
> > > (snip)
> > >
> > > Does this apply to the PA-2013 as well?
> > > I suspect it does, as I always regarded the 2013 as the ATX version of
> > > the 503+, but it would be handy to know for sure before I get hold of
> > > one (to replace my much loved and melted 503+).
>
>

Alex Zorrilla wrote:
> Yup, sure does. Same thing goes for the VA-503A, and just about any
> other MVP3 chipset motherboard.
>
>
>
> Roger Hunt wrote:
>
>> On Tue, 15 Nov 2005, Alex Zorrilla typed this :
>>
>>> The VA-503+ can handle up to 768 MB RAM, consisting of 3 256 MB
>>> DIMMs. The MVP3 chipset can handle a memory density of up to 16 MB
>>> per memory chip.
>>
>>
>> (snip)
>>
>> Does this apply to the PA-2013 as well?
>> I suspect it does, as I always regarded the 2013 as the ATX version of
>> the 503+, but it would be handy to know for sure before I get hold of
>> one (to replace my much loved and melted 503+).

sure the 503A isn't the MVP4 ? ata66 etc

MVP4 is MVP3 with integrated Trident graphics thrown in. Otherwise,
they are basically the same chipset.

You are right about the 503A supporting ATA66 and integrated sound. It
uses the VIA 686A southbridge chip instead of the VIA 596B that is found
in the 503+. They do use the same northbridge, though, which is what is
most often used in naming the chipset.

Maybe they should call it MVP3-1/2. :P



farmuse wrote:
> Alex Zorrilla wrote:
>
>> Yup, sure does. Same thing goes for the VA-503A, and just about any
>> other MVP3 chipset motherboard.
>>
>>
>>
>> Roger Hunt wrote:
>>
>>> On Tue, 15 Nov 2005, Alex Zorrilla typed this :
>>>
>>>> The VA-503+ can handle up to 768 MB RAM, consisting of 3 256 MB
>>>> DIMMs. The MVP3 chipset can handle a memory density of up to 16 MB
>>>> per memory chip.
>>>
>>>
>>>
>>> (snip)
>>>
>>> Does this apply to the PA-2013 as well?
>>> I suspect it does, as I always regarded the 2013 as the ATX version of
>>> the 503+, but it would be handy to know for sure before I get hold of
>>> one (to replace my much loved and melted 503+).
>
>
> sure the 503A isn't the MVP4 ? ata66 etc