computer components & hardware - Memory for M4A88TD-V EVO/USB3

Percival P. Cassidy wrote:
On 06/02/10 09:57 am, I wrote:

Anybody using a M4A88TD-V EVO/USB3 yet? Any recommendations for memory?
More particularly, I suppose, anything that -- even though on the QVL --
did *not* work well?

I bought the mobo and the G.Skill F3-12800CL7D-4GBECO. The BIOS setting
defaults to 9-9-9-24, but it seems to run fine at the rated 7-8-7-24 I
set it to manually -- still at only 1.35v.

Perce

Interesting voltage thing.

I thought the 1.35V operating voltage was a typo on the GSkill site,
but they have an announcement of a series of modules like that.

http://www.gskill.com/news.php?index=239

"G.Skill International Co. Ltd., manufacturer of extreme performance
memory and solid-state storage with solid quality, has today released
its ECO low voltage, 1.35V dual channel DDR3 memory for Intel Lynnfield
Core i5 and Core i7 platforms.

1.35V memory modules produce 16% lower temperatures than standard 1.65V memory."

The DDR3 nominal voltage is 1.5V. Intel processors with integrated memory
controllers, had a 1.65V upper limit placed on them. While other DDR3 devices
(like some chipsets before the Intel processors came along), could run DDR3
at even higher voltages for overclocking. Like perhaps up to 1.8V.

This is a possible source of the lower voltage memory. Micron makes
some chips at 1.35V instead of 1.5V.

http://www.micron.com/partscatalog.h...ltage&fv=1.35V

The question would be, how many Vdimm circuits are prepared to actually
adjust below 1.5V.

I see your board is well prepared. From the manual...

"DRAM Voltage [Auto]

Allows you to set the DRAM voltage. The values range
from 1.20000V to 2.44500V with a 0.01500V interval."

Now, this link is likely useless ("expiretime"), but this is a datasheet
for one of the Micron RAM chips. I was hoping to find an "absolute max"
voltage listed, to see whether overvolting is limited on these
new chips. But the word "absolute" doesn't appear in the document.

http://cache.micron.com/Protected/ex...1_35V_DDR3.pdf

"If the SDRAM is powered up and initialized for the 1.35V operating voltage
range, voltage may be increased to the 1.5V operation range provided:

* Just prior to increasing the 1.35V operating voltages, no further commands
are issued, other than NOPs or COMMAND INHIBITs, and all banks are in the
precharge state
* The 1.5V operating voltages are stable prior to issuing new commands, other than
NOPs or COMMAND INHIBITs
* The DLL is reset and relocked after the 1.5V operating voltages are stable
and prior to any READ command
* The ZQ calibration is performed, tZQinit must be satisfied after the 1.5V
operating voltages are stable and prior to any READ command

If the SDRAM is powered up and initialized for the 1.5V operating voltage range,
voltage may be reduced to the 1.35V operation range provided:

* Just prior to reducing the 1.5V operating voltages, no further commands are issued,
other than NOPs or COMMAND INHIBITs, and all banks are in the precharge state
* The 1.35V operating voltages are stable prior to issuing new commands, other than
NOPs or COMMAND INHIBITs
* The DLL is reset and relocked after the 1.35V operating voltages are stable and prior
to any READ command
* The ZQ calibration is performed, tZQinit must be satisfied after the 1.35V operating
voltages are stable and prior to any READ command"

Neat. That probably doesn't happen in normal operation anyway. Once the
BIOS has set things up, the RAM probably isn't turned on until the other
settings are ready to go. RAM doesn't start the instant that power
is applied. The RAM controller has to be programmed first, and that
could be some period of time after t=0.

I don't see a particular reason to panic. I'm just curious what would
happen to those modules, if they're cranked to 1.8 volts. Right now,
I don't have any data to go on.

Since they're calling that "DD3L", it's possible other manufacturers
are making some as well.

There is a road map for it. Now I can see why the Asus BIOS adjusts
down to 1.2V.

http://www.brightsideofnews.com/news...-of-ddr3!.aspx

"1.2 volt DDR3 in 2011"

Paul