A7V266-E - No more support ?

  • Thread starter Thread starter Coolasblu
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My board as well :)

What support do you need ?

Mines humming alone with an Xp 2400 1 gig DDR PC2100 :)
 
We Live For The One We Die For The One said:
My board as well :)

What support do you need ?

Mines humming alone with an Xp 2400 1 gig DDR PC2100 :)
Click to expand...


Well I can't seem to get above 512Mb to work. currently yhave 2 x 256MB
Crucial PC2100 DDR. Have tried adding 512MB crucial PC2100 DDR which caused
crashes, then added 1024GB stick of PC2100 DDR and this did the same but
only 512Mb of it was recognised!
 
Well I can't seem to get above 512Mb to work. currently yhave 2 x 256MB
Crucial PC2100 DDR. Have tried adding 512MB crucial PC2100 DDR which caused
crashes, then added 1024GB stick of PC2100 DDR and this did the same but
only 512Mb of it was recognised!
Click to expand...

The KT266A Northbridge looks to be very flexible. The Asus manual says
the board will run with unbuffered modules or registered modules, but
you cannot mix the two types on the board at the same time. I doubt you
bought a 1GB registered module, but you might check that.

With the 2x256 modules and the 1x512 module, I would put the 512MB
module furthest from the processor (i.e. next to the termination resistors).
That is the best you can do in terms of electrical loading.

The BIOS seems to have lots of options for setting up the ram manually.
There is a command rate setting, and while the BIOS should set command rate
to 2T in the presence of multiple DIMMs, you could try setting it manually
to 2T. You could also try relaxing the timings a bit.

(SDRAM Config = User defined. Next four settings = 3 3 3 6 or whatever the
max that the BIOS offers for each. See if that is enough to give error free
performance by using memtest86.)

With respect to the 1GB module, you are undoubtedly a victim of the "stacked
RAM" scam. Many people, when shopping for ram, will notice Kingston or other
branded 1GB rams being very expensive ($250+), then notice some generic 1GB
module for $150. As far as I know, these "stacked" rams are not an approved
configuration by JEDEC and are not expected by desktop motherboard
manufacturers.
In fact, I don't know of any motherboards that are purpose built to drive
these modules, so this begs the question of why these modules are being sold
at all. I like to think it is because disreputable vendors want you to return
the module and be stuck with "store credit" or a restocking fee.

The Mushkin website has a webpage devoted to their testing of the 1GB "stacked"
ram that they sell. Unlike other vendors, they are very honest that they are
selling a 'stacked" product, so they aren't hiding the fact. If you go to
Mushkin.com, click "DDR SDRAM", then "DDR Mainboard Qualification Page",
then "Click Here For 1GB Compatibility Qualification", you can read all about
it, including the suggestion of using 2T command rate.

In terms of module design, the easiest way to get 1GB/2GB/4GB modules to work,
is to used registered ones. The register chip on the module buffers the
memory address from the Northbridge, and this significantly eases the job of
making a working memory subsystem. Usually, registered modules only work on
server boards (and now, I think some Athlon FX boards are using registered
as well). Reading accounts in google of the A7V266-E, the use of registered
in this board appears to be problematic - it works for some people and not
for others.

Normally, you would use the more available unbuffered modules. To stand a
better chance of getting a 1GB module to work, you should be buying a module
with 16 chips, each of which is 64Mx8 in dimension. In other words, it is
like a 512MB module that uses (16) 32Mx8 chips, only the chips are twice
as deep. The bus loading of the two module designs is then identical.

When you buy the "stacked" memory modules, then the address loading or
the control signal loading can be doubled. This is fine, if the chipset
has the ability to adjust drive strength and timing for such a module,
but most desktop motherboards won't be up to the task.

Your description of only half the module showing up, is to me a kind of
proof that a 128Mx4 or deeper chip is being used. The Northbridge is
probably missing the address bit necessary to address this deeper chip,
and that is why only 512MB is detected.

So, I would return to your 2x256 + 1x512 experiment, and try relaxing
the timing. Return the 1GB module for a refund. Then, visit crucial.com,
kingston.com, or corsairmicro.com, and look at the datasheets for the
1GB modules they sell. (The Corsair modules are new and may not be in
stores yet.) You will pay a lot more, depending on what speed you buy,
but you stand a chance of getting the 64Mx8 chips that just might work.

Crucial is a part of Micron and sells Micron modules with the Crucial
label on them. Scroll to the bottom of this page, to see how they
build 1GB modules (i.e. with 64Mx8 chips):

http://www.micron.com/products/modu...count=184-Pin&version=Unbuffered&package=DIMM

With Kingston, when you get to a page like this one:

http://www.ec.kingston.com/ecom/configurator/PartsInfo.asp?ktcpartno=KVR266X64C25/1G

you can click the "Datasheet" button, to get a PDF description of the module:

http://www.valueram.com/datasheets/KVR266X64C25_1G.pdf

On the Corsair site, click on the part number in the list, to get the
datasheet for the module, for example the CMX1024-3200 module:

http://www.corsairmicro.com/corsair/xms.html
http://www.corsairmicro.com/corsair/products/specs/cmx1024-3200.pdf

Good luck (you'll need it),
Paul
 
Normally, you would use the more available unbuffered modules. To stand a
better chance of getting a 1GB module to work, you should be buying a module
with 16 chips, each of which is 64Mx8 in dimension. In other words, it is
like a 512MB module that uses (16) 32Mx8 chips, only the chips are twice
as deep. The bus loading of the two module designs is then identical.
Click to expand...
Thanks for your excellent reply Paul!

My 1gig stick has 16 chips, with 128MX4T4 P -75 printed on each chip. =
1024gb, ddr, 266Mhz

The crucial 512Mb stick has : 46V32M8 on each of its 16 chips. = 512mb ddr,
266Mhz, CL2.5 = same spec as the 2 256MB crucial chips in the machine.

Any ideas ? P.S. I have ordered an ANtec PSU to see iof that helps and am
awaiting an RMA number for my 1 GIG stick.
 
Thanks for your excellent reply Paul!

My 1gig stick has 16 chips, with 128MX4T4 P -75 printed on each chip. =
1024gb, ddr, 266Mhz
Click to expand...

I think that means the 16 chips behave like a single "bank" or side of
a conventional DIMM. A bank is always 64 bits wide, and can be made
using (8) x8 chips or (16) x4 chips (or even (4) x16 chips). I cannot
say whether your chipset supports the 128M size of those chips (as
there isn't a datasheet to read), and if the most significant
address bit is missing from the chipset, that is why the module only
registers as 512MB.
The crucial 512Mb stick has : 46V32M8 on each of its 16 chips. = 512mb ddr,
266Mhz, CL2.5 = same spec as the 2 256MB crucial chips in the machine.

Any ideas ? P.S. I have ordered an ANtec PSU to see iof that helps and am
awaiting an RMA number for my 1 GIG stick.
Click to expand...

The power consumption of RAM is pretty low, and I wouldn't expect
adding ram to make a difference. When you have three DIMMs in a machine,
two of the DIMMs are drawing "idle current", while the third is active.
That means the power consumption caused by the addition of a second and
third DIMM doesn't increase linearly. A DIMM with an industry standard
access pattern applied to it, draws about 5 watts. The added DIMMs would
be less than that, each.

So, what problem are you having now ? Are you currently trying to
get the 2x256 + 1x512 working ? I don't think there is any point
trying to work further with the 1GB module.

I guess you said "Have tried adding 512MB crucial PC2100 DDR which
caused crashes". Have you tried experimenting with the RAM timing
in manual mode ? At PC2100 rates (DDR266), you should be able to
have three sticks, so it should work without too much trouble.
Have each of the three modules been tested separately, to make
sure there isn't a problem with one of the modules ? Maybe you
should try memtest86 on each one first. Then, put the 512MB
module furthest from the processor and install the other two
256MB modules next to the processor. Relax the ram timing, until
you can at least establish that the modules can be made to work
error free.

I went to the Mushkin website, and they have a motherboard
qualification webpage inside the DDR SDRAM section. It has this
to say about the A7V266-E:

"We have qualified the ASUS A7V266-E as a representative board
of the VIA KT266A chipset-based mainboards. All PC2100 DDR DIMMs
offered by Mushkin Enhanced are running 100% reliable and stable
on the A7M266 using 2 x 128 and 256 MB DDR DIMMs. With 512 MB DIMMs,
the latencies have to be relaxed to 2,5:3:3; 2T CMD Rate tRAS=6.
With the Level2 222 DIMMs, this cautionary statement does not
apply, we have run the A7V266-E at 2:2:2-6T 1 T CMD rate with
2 x 512 MB as long as the modules were used in DIMM slots 1 and 3.
Using 3 x 512 MB we have been running the A7V266-E stable
but it depends on the speed grade of the memory what latency
settings need to be relaxed for total stability."

Since your modules are CAS 2.5 as well, try the 2T CMD Rate
setting.

You also have JP! and JP2 to play with. At these speeds, the 2.65V
default jumper setting should be enough to get the ram to work. If
none of the manual ram timing settings help, you can try playing
with JP1 and JP2.

HTH,
Paul
 
Fantastic information to work with. I've printed this out and will get back
to you Paul. Thanks for the time and effort!

be intouch
 
Have installed the 512MB stick in the slot furthest from CPU. So far so
good. Haven't touched any settings in the BIOS so far. Here are the current
settings:

SDRAM Config = By SFD
SDRAM CAS Latency = DDR 2T
SDRAM RAS Prechange = 3T
SDRAM RAS to CAS = 3T
SDRAM Active to Prechange = 6T

DDR 1T/2T ITEM = 2T CMD

Should the 3T's be changed to 2T ?
I will leave as is and try and install the 2 256Mb stocks one by one in the
remaining bays. BTW, couldn't burn the memtest86 image. What do I need ? I
have NERO 6.

TIA

Ravi
 
Have installed the 512MB stick in the slot furthest from CPU. So far so
good. Haven't touched any settings in the BIOS so far. Here are the current
settings:

SDRAM Config = By SFD
SDRAM CAS Latency = DDR 2T
SDRAM RAS Prechange = 3T
SDRAM RAS to CAS = 3T
SDRAM Active to Prechange = 6T

DDR 1T/2T ITEM = 2T CMD

Should the 3T's be changed to 2T ?
I will leave as is and try and install the 2 256Mb stocks one by one in the
remaining bays. BTW, couldn't burn the memtest86 image. What do I need ? I
have NERO 6.

TIA

Ravi
Click to expand...

You would have to download a datasheet for your Crucial DIMM from the
Micron site. I got the MT16VDDT6464AG-265 datasheet from here:

http://www.micron.com/products/modu...count=184-Pin&version=Unbuffered&package=DIMM

A -265 PC2100 stick has:

Tcas = 2 cycles*7.5ns each ( 7.5ns = 133MHz clock = DDR266 )
Trp = 20ns (divide by 7.5 needs 3 whole cycles = 3T)
(Trrd = 15ns ???)
Trcd = 20ns (divide by 7.5 needs 3 whole cycles = 3T)
Tras = 45ns (divide by 7.5 needs 6 whole cycles = 6T)

so the 3T values look valid. You have to round up to the next nearest
integer value.

The BIOS should use the slowest stick, to set those default timings.

I cannot help with the memtest thing, as I always use a floppy.

HTH,
Paul
 
So far so good. I have placed the 512 stick in the slot furthest from the
processor and the other 2, 256 sticks in the other two slots. Have run
various games and 3dMark2001 and no crashes. Its been running for several
hours now and seems stable.

Fingers crossed and alls ok. It seems chosing the right socket for the 512
stiick made all the difference.

Thanks Paul for your help. Will let you know if things go wrong again. I now
hav 1Gig RAM working! Will return the PSU I ordered as well!

Ravi
 
I guess I spoke too soon.

twice now winxp has crashed causing a spontaneous reboot and both times were
while using Adobe Photoshop CS. I have set PS to use my seocnd drive as its
scratch disk.

The first time it crashed, windows couldn't restart as there was a missing
c:\windows\system32\config\system file. In recovery console I could see the
file but didn't know how to fix it. So I reloaded a ghost image I had taken
a couple of days ago. I then opened up PSCS and after doing some minor
editing the same thing happened, but this time chkdsk repaired the faults
and I could restart windows.

Do you think this is due to a memory problem or a software problem? It does
seem odd that all was fine when running 2 x 256MB slots. In fact things were
going well this week right up until today. I was editing big files in PSCS
and playing Call Of Duty with no problems.

It just seems weird.....

Any tips ?
 
I guess I spoke too soon.

twice now winxp has crashed causing a spontaneous reboot and both times were
while using Adobe Photoshop CS. I have set PS to use my seocnd drive as its
scratch disk.

The first time it crashed, windows couldn't restart as there was a missing
c:\windows\system32\config\system file. In recovery console I could see the
file but didn't know how to fix it. So I reloaded a ghost image I had taken
a couple of days ago. I then opened up PSCS and after doing some minor
editing the same thing happened, but this time chkdsk repaired the faults
and I could restart windows.

Do you think this is due to a memory problem or a software problem? It does
seem odd that all was fine when running 2 x 256MB slots. In fact things were
going well this week right up until today. I was editing big files in PSCS
and playing Call Of Duty with no problems.

It just seems weird.....

Any tips ?
Click to expand...

How did the testing go with memtest86 ?

As for adjustments, about all you can do is relax the memory timings,
reduce the frequency (which sucks), bump the DIMM voltage. You should
be using memtest86, because it is a lot harder to detect memory
problems by waiting for the OS to crash.

I am the kind of person, that rather than solve the problem, I
like to study it and learn from it. First off, I would try the
DIMMs one at a time, and crank up the timings and frequency, to
see whether each DIMM is good and has some margin over and above
its ratings.

With one DIMM in the machine (and stable memory as far as
memtest86 is concerned), I would then boot into Windows and
test the CPU with prime95 or a similar utility. Just on the
off chance that the processor itself isn't stable or maybe needs
a Vcore adjustment. There is no need to play with Vcore if the
processor can run 100% load like this without problems (after
all, it would only heat up the processor unnecessarily).

So, what I am suggesting, is test the various parts of the
system, one at a time. That is the only way to narrow down
where the problem really is.

Also, when Prime95 or other testing utilities are running, use
MBM5 or Asus Probe to monitor system voltages. A little variation
is OK (5%) and Vcore will "droop" whenever the processor is
going 100%.

HTH,
Paul
 
Never had any problems at all with my Asus P3B-F with 512Mb!!!! God I miss
that board. Ok it only had a PIII 500Mhz in it but it did its job well and
never caused problems no matter what I installed in it......
Right up until my wife spilt a jug of water over it!!!!......

Still working on things now....
 
OK latest update:

Just run memtest86 for over 12 hours and no errors or crashes
Prime95 ran for a fwe hours with no crashes.

I wonder if this is a software issue or a graphics card communicatoin error
?
 
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