I've heard various things about DDR2 and its energy efficiency/lack
thereof. Well, first of all, I've heard that DDR2 uses lower voltage
than DDR1, which usually means lower power consumption. But then
someone said that there is a lot of built-in resistance inside a DDR2
module which sucks out a lot of current, which again raises its Watts
consumption. Recently I've also heard that video card manufacturers are
bypassing GDDR2 in preference for GDDR3, because of GDDR2's power
consumption.

What to believe?

Yousuf Khan

On 4 Jan 2005 13:09:27 -0800, "YKhan" <(E-Mail Removed)> wrote:

>I've heard various things about DDR2 and its energy efficiency/lack
>thereof. Well, first of all, I've heard that DDR2 uses lower voltage
>than DDR1, which usually means lower power consumption. But then
>someone said that there is a lot of built-in resistance inside a DDR2
>module which sucks out a lot of current, which again raises its Watts
>consumption. Recently I've also heard that video card manufacturers are
>bypassing GDDR2 in preference for GDDR3, because of GDDR2's power
>consumption.

Conflict Alert. Comparing what graphics engines desire for memory
characteristics will not shed much light on what platform engineers desire for
memory characteristics.

>What to believe?

Component vendor specs - IDDmax_operating for dimms of the same capacity and
geometry, for instance?

It should take you about 10 minutes to find out what Micron, for example, has
to say on this specific subject...

/daytripper (imo: the IDD advantage of the winner is not subtle...)

YKhan wrote:
> I've heard various things about DDR2 and its energy efficiency/lack
> thereof. Well, first of all, I've heard that DDR2 uses lower voltage
> than DDR1, which usually means lower power consumption. But then
> someone said that there is a lot of built-in resistance inside a DDR2
> module which sucks out a lot of current, which again raises its Watts
> consumption. Recently I've also heard that video card manufacturers are
> bypassing GDDR2 in preference for GDDR3, because of GDDR2's power
> consumption.

Ohm's Law shows that watts = volts squared over ohms. So lower voltage
and higher resistance would both mean vastly lower power draw.

All that tells me is that your characterization is incorrect, and
doesn't let me help a bit with an answer, sorry.

--
bill davidsen ((E-Mail Removed))
SBC/Prodigy Yorktown Heights NY data center
Project Leader, USENET news
http://newsgroups.news.prodigy.com

On 4 Jan 2005 13:09:27 -0800, "YKhan" <(E-Mail Removed)> wrote:

>I've heard various things about DDR2 and its energy efficiency/lack
>thereof. Well, first of all, I've heard that DDR2 uses lower voltage
>than DDR1, which usually means lower power consumption. But then
>someone said that there is a lot of built-in resistance inside a DDR2
>module which sucks out a lot of current, which again raises its Watts
>consumption. Recently I've also heard that video card manufacturers are
>bypassing GDDR2 in preference for GDDR3, because of GDDR2's power
>consumption.
>
>What to believe?
>
> Yousuf Khan

Does this help any?
http://www.micron.com/products/dram/syscalc.html

Ed