In article <(E-Mail Removed)>,
"alexr" <(E-Mail Removed)> wrote:
> Mainboard : Hewlett-Packard (3085)
> Chipset : ATI Radeon RS480
> Processor : AMD Athlon 64 3500+ @ 995 MHz
> Physical Memory : 512 MB (2 x 256 DDR-SDRAM PC2700 @ 166 MHz)
> Video Card : ATI Technologies Inc Mobility Radeon XPRESS 200
> Hard Disk : ST9100822A
> Network Card : Broadcom Corp BCM4306(??) 802.11g Wireless NIC
> Network Card : Realtek Semiconductor RT8139 (A/B/C/810x/813x/C+) Fast
> Ethernet Adapter
> Operating System : Microsoft Windows XP Home Edition 5.01.2600 Service
> Pack 2
> DirectX : Version 9.0c
>
> Hi,
>
> I recently got a new laptop (a compaq presario r4125). The system specs
> are below. My question: Is the RAM acting as a bottleneck, slowing the
> computer down? I read the following review for a similar laptop where
> the author had concerns about the RAM, i'm not sure if this would apply
> to my laptop also http://www.epinions.com/content_190050045572 . So did
> i get screwed on this laptop?
>
> Also if i'm going to be adding another 512 megs of memory, is there a
> particular type of RAM i should get?
>
>
> Thanks.
If you want an estimate, without any corroborating evidence, I
use a "1/3rd rule". Take the ratio of the RAM speeds. 400/333 = 1.20,
a 20 percent difference. Your applications will suffer from
0 - 6.6% performance loss, by using the slower memory. The
zero percent case happens when a task is CPU bound. The 6.6% case
(or perhaps a bit higher) will happen with something that accesses
more memory. I think a compression application might tend to be
6 or 7% slower. This estimate doesn't take into account the effects
of using command rate 1T versus 2T timing, or the effects of
CAS2 versus CAS3 memory. This estimate also doesn't tell you what
happens when using synthetic programs, like benchmarks - a bandwidth
benchmark will not follow this rule of thumb at all. This rule of
thumb is intended for real applications.
If you wish to play with the laptop, get a copy of A64tweaker.
This allows some parameters to be adjusted, while sitting in
Windows. I don't believe you can actually change the CAS setting
while the computer is running, and perhaps a copy of CPUZ (cpuid.com)
or Everest Home Edition (lavalys.com) can be used to observe whether
a given setting change is actually working or not. You should use
a benchmark program of some sort, to verify that A64tweaker has
actually changed the behavior of the hardware. (Something with
a slight memory bandwidth dependency would be nice.)
A64Tweaker (latest version I've heard of)
http://home.exetel.com.au/codered/A6...r_V0.6beta.zip
A64Tweaker developer thread
http://www.xtremesystems.org/forums/...threadid=37345
Download links listed here as well, with comments on best version:
http://xtremesystems.org/forums/show...532#post711532
Here is a picture of A64tweaker - you will be changing the
memory frequency in the lower right - increase it from
166 to the next highest setting, which might be ~180 or so.
Then, if the computer doesn't lock up, run your test program(s),
and see what the real gains are. Chances are, if you are not
too aggressive with the memory clock setting, you'll avoid
a crash.
http://www.xtremesystems.org/forums/...chmentid=14809
Any time you do experiments like this, make sure your hard drive
is backed up first. You can never be too safe...
Paul