KT600 vs nForce2

Wolfie

Hi Lads,

Skip to ***** below to avoid the tale of woe which resulted in my questions.

Had an eventful day today, when DVD burner, new CPU fan and Xaser3 case arrived... Got a cheapo Spire Whisperock instead of my noisy ass Jet7, and popped that in. Put the fan in my old machine last night, worked fine, but today got the new case and transferred all my stuff across. The spire heatsink was a real pain in the ass to remove... I had to remove it to put a heat probe under the CPU for the Xaser case, and had to put a lot of pressure on the CPU to no avail... I used a small pen knife for leverage, and then *snap!* the knife slipped, cut my finger and stabbed the motherboard.

When everything was put into the Xaser case, I went to power on my machine.. no joy. Power was going to the motherboard, but the power switch was not working and I was getting no display. Long story short, using other parts, I think my motherboard and/or processor are knackered.. I'm running from my old 1.2ghz Thunderbird now.. hehe. Anyway, obviously I need a new motherboard / processor for my rig, so my questions are:

***************

My old mobo chipset was KT400. I was sorry I didnt get the nForce2 of course. Is the nForce2 still better than the newer KT600? If so, why?

My existing ram is PC3200, will I notice a real difference using it on a 400mhz bus as opposed to 333?

Thats all... Oh, and I'm on a budget, so no recommending getting dual athlon 64's or the like! The damn xaser case emptied my pockets, and now it ends up costing me more!! ARGH!

bizmark

damn man i know how you feel myself build doesnt work right either

Wolfie

Yeah Bizmark, its the pain of modding! now I'm wondering if I should abandon AMD and splash out the extra on a P4 with 800mhz FSB, as opposed to 400mhz with AMD and nForce2. Anyone got any advice?

Woden

yeah nforce2 is still the chipset of choice for an XP system

sample benchmark

http://anandtech.com/mb/showdoc.html?i=1858&p=9

po0k

Originally posted by Wolfie
Yeah Bizmark, its the pain of modding! now I'm wondering if I should abandon AMD and splash out the extra on a P4 with 800mhz FSB, as opposed to 400mhz with AMD and nForce2. Anyone got any advice?

The FSB on the latest P4s and Barton XPs is still 200Mhz, but the P4s are quad-pumped, the XPs being only dual-pumped.
If you've got dual-channel DDR (2 matching sticks) of PC3200, the P4 will make the most of it in memory bandwith at least, whereas you'd only see a 3-5% perf increase on the Barton (the dual channel essentially filling up whatever overhead space was left by single-channel).

As you're on a budget I'd say go for AMD and a decent nForce2 setup.
I'm probably wrong but isn't the XP2500 a FSB166 chip that scales well to FSB200, maybe in conjunction with a lowering of the multiplier to improve stability?
Could be a cheap path to FSB200.

Woden

Originally posted by SyxPak


As you're on a budget I'd say go for AMD and a decent nForce2 setup.
I'm probably wrong but isn't the XP2500 a FSB166 chip that scales well to FSB200, maybe in conjunction with a lowering of the multiplier to improve stability?
Could be a cheap path to FSB200.

yeap this is correct however the lastest 2500+'s are all multi locked but chances are he can overclock it to 200*11 and get xp3200+.

question what does this dual and quad pumping do? how important is it? and why don't amd quad pump if its better? and why don't they keep scaling up this pumping?

po0k

Originally posted by Dataisgod
yeap this is correct however the lastest 2500+'s are all multi locked but chances are he can overclock it to 200*11 and get xp3200+.

question what does this dual and quad pumping do? how important is it? and why don't amd quad pump if its better? and why don't they keep scaling up this pumping?

You know the way you say DDR memory at a clock of 200Mhz (FSB speed) is "running" at 400Mhz? (PC3200)
The ram transfers data twice per clock cycle, or is "double-pumped".
It would appear to be two banks/channels of ordinary SDRAM to the memory controller.
When you have two channels of DDR memory, you're effectively getting 4 data transfers per clock.
The Pentium 4 has 4 memory access streams through which it transfers data to and from the RAM.
The athlon was designed before dual-channel DDR was common-place in the consumer market and I suspect the engineers didn't forsee it alsting as long as it did.
For them to reengineer it to run with dual-channel DDR (quad-pumped) would require a redesign of the socketA, new chipsets (northbridge in particular) and a retooling/reconfig of the assembly line, all of which would cost far more than they could realistically make back (even a few years ago) while still using the same core tech.

One place AMD could have taken advantage of dual-channel was the chipset for the MPs, as memory bandwidth is one place where they were lacking against Intel's offerings (which also had high-performance custom 3rd-party chipsets from ServerWorks).
Giving a seperate DDR channel to the MPs would've helped them an aweful lot as they were truely great little chips had they been scaled alongside the XPs.

Woden

thanks for the info.

and is there technical limitations, why is there not Quad DR ram for example?

po0k

Wouldn't amke a difference to Athlons, as they can't handle more than 2 "pumps".

And afaik there is/was some experimentation with QDR SDRAM. Don't think it was very successful though.
It may in fact have been RAMBUS which would tie-in nicely with the first-gen P4s being Quad-pumped and having chipets which only supported RAMBUS.
Afaik RAMBUS was 4x 16-bit pipes at high frequicences (800Mhz, 1066Mhz or something). Had very high latencies compared to DDR due to the way the modules were checked, 3 out of every 4 went into a sort of "sleep" mode for every cycle or something to conserve power.
Google and you'll find out the specifics.
DDR2/3 are the newer incarnations of DDR, running at lower voltages and higher frequiencies and afaik lower pin-counts.

Wolfie

Thanks for the info Syxpack and Data, I often wondered about the FSB differences between the two. At the moment I have only one DDR PC3200, so maybe the quad pumping wouldnt be so much of an issue.. but out of interest, you say that with an Athlon and two DDRs one would expect 3-5% memory performance increase, what would you get with a P4? Double that I'm thinking?

And If I get another stick of Crucial PC3200, will it work ok, as I see that you can buy them in matched pairs?

secret_squirrel

You're prolly better off running paired ram, but Im running paired in 1 pc and non-paired (but same make/spec) in the other - with no differences between them.

Certainly not worth binning/selling your current stick to get a paired set though.

Although I think Im right in thinking that crucial memory had a problem in early nforce2 boards. Im sure its been long sorted tho...????

Woden

i'd run paired ram in the sense that i'd run two sticks from the same manufacturer, so i bought one stick of 512mb last november with the intention of buying another one if needed.

however i don't buy into the whole dual-kits they have going, with specially selected ram thats guaranteed to work together tis all a lot of bollox imo just a marketing thing, its fine if you want a gig of ram then i'd buy a 2*512 set but if i wanted 512mb i'd stick with one chip with the option of going dual channel later if you want to.

my main reason for sticking with the same ram though would be because i have a transparent case side and it would look crap if i had to different sticks

tman

Originally posted by Dataisgod
however i don't buy into the whole dual-kits they have going, with specially selected ram thats guaranteed to work together tis all a lot of bollox imo just a marketing thing, its fine if you want a gig of ram then i'd buy a 2*512 set but if i wanted 512mb i'd stick with one chip with the option of going dual channel later if you want to.

aye, thats what i did.
bought one stick of 512mb pc3200 off komplett & have kept track of the sku number for upgrading to 1024mb in the near future...

Myg

Syx: DDR2 uses 240 pins instead of DDR's 184, just a slight correction.

po0k

I meant lower pin-counts on the actual chips themselves, though not having researched any info on DDR2/3 I can't say for sure.
Where I'm getting this idea is a report from ElReg which mentioned DDR2 modules having ~1.6Gig bandwidth per pin and aggregate bandwith of ~6.4Gig per module or something along those lines.

Wolfie - running dual channel DDR on a P4 will give you ~90% increase in memory bandwidth, simply because you've got twice as many possible transfers per clock.
That doesn't neccessarily mean that everything will be boosted by ~90%, but more memory bandwidth is a nice thing to have .

secret_squirrel: what chips are your PC1 (DC DDR) and PC2 (SC DDR) running??

w.r.t. running mixed modules, as ,ong as your running them both at the highest common factor timings (ie at the speed and timings of the slowest module) they should both be fine in dual channel, regardless of manufacturer.
Obviously you could get 2 sticks which don't want to play ball, but ram is manufacturerd to a standard and therefore all ram from the same class should be intermixable, though again for peace of mind you might just want to go for homogenous modules.

I'm currently running a 128meg PC100 CAS2 stick and two 256meg PC133 CAS3 sticks all at PC100 CAS2.

unkel

Originally posted by Dataisgod
if i wanted 512mb i'd stick with one chip with the option of going dual channel later if you want to.

That's cause you'd hardly notice the difference on an AMD xp setup. Biggo difference on a P4c though

secret_squirrel

All the memory is twinmos PC3200 cas 2.5 - 2x256mb in 1 pc and 2*512mb (matched) in t'other. Its the cheapest 'name' brand komplett did

Plus all I wanted was to hit 200FSB for my XP2500's to make Xp3200's

po0k

so both machines are AthlonXP 2500s?

Well that's why you're seeing hardly any performance gain between single and dual channel DDR.