"^JR^" said:
I think you misunderstood the question. I'm aware of everything you said.
I'm wondering about the performance of DDR vs. regular SDRAM. With DDR
being much faster, how well would 256 meg DDR handle the load that my
current 512 meg of pc133 does? I ultimately want to get 512 meg DDR total
when I get a new motherboard, but the money doesn't allow for that right
now.
I think you misunderstood the answer.
Storage in computers is done in "layers". L1 and L2 Cache, system memory,
and the swap file on the hard drive are the levels. Each level is
significantly slower than the one before it. Spillover, from one layer
to the next, occurs when the memory is full. As Madonna explained,
checking the System Info to see how much system memory is being used,
is a good indication of how much slowing of the system will occur.
Chances are 512MB was too much for your previous system, so there
was no need for information to spill over into the
swap file. The 256MB might be enough for all but the most demanding
application. You will find some games which have huge memory footprints,
and these might be the only things that won't run well. Also,
applications like Photoshop, which needs 5X the image size to hold
the image files in memory, are very demanding of total memory size.
If you are just surfing, doing email, using Microsoft Office applications,
the 256MB will be fine, and you won't notice any slowdown.
So, there are two effects. The difference in clock rate between
SDRAM and DDR SDRAM affects each and every cycle done on the System
Memory and affects the performance of the system at all times. The size
of the memory affects how often the computer has to get its information
from the slow swap file on the computer disk, rather than from System
Memory. The size issue will only slow you down if the memory is full,
and only you can decide what kind of applications you run and how big
their memory footprint happens to be (large games, Photoshop, video
editors, are memory pigs).
So the answer is not a simple one.
Your options are:
1) Test the current system and see how full the memory gets. Buy
enough memory on the new system for the most demanding set of
applications you expect to run simultaneously.
2) Blindly buy 256MB of memory now for the new system. Try the
system out, and if it "feels slow", buy some more memory.
HTH,
Paul