One of the things holding back the AthlonXP, is memory bandwidth.
The front side bus on the AthlonXP really only has enough bandwidth
to mate usefully with single channel RAM. So, even if you went from
an A7V8X to an A7N8X-E Deluxe (which has dual chahnel), the FSB only
has enough bandwidth to work with a single PC3200's worth of
bandwidth. (FSB400 times 8 bytes per transfer on the processor's
64 bit bus, yields 3.2GB/sec bandwidth - that is equal to the
bandwidth of a single PC3200 DIMM. If the FSB could be pushed
to FSB800, dual channel DDR400 would make more sense.)
Now, consider the P.R. rating of the processors you are talking
about. You are considering moving from a 2600 to a 3000 or a 3200.
This is "small potatoes". Not worth the expense for such a tiny
increment in performance.
It is time to consider what another platform can do for you.
As a gamer, AMD is the right solution for building a gaming
platform. It really all depends on what kind of a budget you
have available. If you are really attached to the 9800 video
card, then a socket 939 with AGP slot might be the right
answer. Otherwise, look for a socket 939 board with PCI Express
video slot. I don't consider SLI to be a necessity, as you
can do pretty well with a single card, if you get the right
card. (And consider how expensive it is to upgrade from one
pair of SLI cards to another pair of SLI cards...)
For the processor, you want to select one which overclocks well.
You don't have to buy a 4000+ to get top performance, and you
can look for a lesser processor and overclock it. Visit the
private forums like
http://www.xtremesystems.org/forums/ or
forums.pcper.com and perhaps if you read a few thousand posts
there, you'll get a better idea as to which exact socket 939
processor stepping, makes the best choice for overclocking.
For memory, your socket 939 board will have four slots, but
as an overclocker, plan on only ever using two of them.
Either buy 2x512 or 2x1GB DIMMs, for a total of 1GB or 2GB
of memory. Regardless of platform, one DIMM per channel is
the right number to use if you plan on overclocking, and
tapping into extra memory bandwidth that way never hurts.
The reason I haven't mentioned S754 as a solution, is it is
still single channel, and while it may impress you as a solution
for a few weeks, you'll want to upgrade it a year from now.
It is possible you'll get a little extra time out of the
S939 board. If you go for a PCI Express based motherboard, then
at least you know that there will be better future video cards
for you to upgrade to.
You could also try overclocking your current board, and by
doing that, you'll get some idea of just how much a processor
upgrade would be buying you. Run a copy of 3DMark at nominal
clock speed, then try a mild overclock and run the test again.
That will tell you what to expect from a minor processor
upgrade, without wasting any cash.
For some numbers, Tomshardware has their CPU charts. They use
a 6800GT video card, with a variety of processors.
http://www.tomshardware.com/cpu/20041221/cpu_charts-15.html
UT2004 Percent_change P.R._%_change
AthlonXP 2600+ Tbred 97.8 FPS 0.0 0.0
AthlonXP 2600+ Barton 98.2 FPS 0.4% 0.0
AthlonXP 3000+ Barton 105.0 FPS 7.4% 15.4%
AthlonXP 3200+ Barton 113.6 FPS 16.1% 23.1%
Athlon64 3500+ Winchester 146.2 FPS 49.5% 34.6%
Note that, for the AthlonXP, the real change is less than the
improvement in P.R. number. With the Athlon64, you can see the
platform has made more of a difference than the P.R. rating
alone can account for.
Something that was bothering me in the charts above, is it looked
like the S754 P.R. ratings were doing better than the S939.
(3400+ S754 better than 3500+ S939.) I suspect the difference
is the cache inside the processor. These two pages might help
make that clearer. I like the fact, that in this review, the
S754 and S939 both use NF3 250 chipset motherboards, so the
chipset can be removed as an excuse.
http://www.xbitlabs.com/articles/cpu/display/29cpu-hl2_2.html
http://www.xbitlabs.com/articles/cpu/display/29cpu-hl2_4.html
There was a time, when I would only have considered upgrading
if I could get a 100% improvement in performance. An FX-57
might make that close to being possible, but you'd need a
pretty big budget, to improve both the processor and the
video card. You could consider putting your upgrade money
in the bank, until you have enough to afford a real upgrade,
being aware that in computing, a dollar doesn't buy as much
improvement as it used to.
http://www.xtremesystems.org/forums/showthread.php?t=44571
In the above, I haven't even mentioned dual core, as it is
much too early to invest in it. Once good multithreaded
games become available, it'll become worth discussing.
Maybe two years from now.
HTH,
Paul
