Ram maybe bottlenecking my northwood p4?

[quantumsheep]

My Northwood currently at 3.6 ghz with 125 fsb is using pc2700 ram. Would getting some better ram (pc4000 or somethign similar) increase the perf of my cpu at all?

Any help would be much appreciated!

QuantumSheep

 

[SidVicious]

It really depends on the chipset that your emachine is based on, any single-channel solution will starve your CPU of memory bandwidth.

Regardless, are you sure that your 2.8GHz Northwood is really a 400FSB piece ? The fastest retail Northwood that ran on a 400FSB was the 2.6G model, otherwise, the 2.8G and 2.8C respectively run on a 533 and 800 FSB.

Also, I could'nt find any information on a 3230 emachine, are you sure that you got the model number right ?

BTW, that's a nice set of machines that you got, have you considered joining the THGC Folding@Home team ?

 

[Scougs]

You didn't say what speed you are running your ram at. It also matters if you motherboard supports dual channel memory. Usually your best performance will be with the memory and fsb at the same speed. However, with a Pentium 4 and only single channel you might benefit from having the memory run faster than the fsb if you can set it up that way.

If you truly have a 400fsb 2.8 then your multiplier is 28.
The weird thing is that 28x125=3.5 not 3.6
Which is it?

At stock your CPU's theoretical fsb bandwidth is 3200 MB/s
At 125fsb you CPU's theoretical fsb bandwidth is 4000 MB/s
I guess if your motherboard only supports single channel memory and you can actually run memory at DDR500 while your fsb is only 125MHz, PC4000 might give you the best performance.

 

[quantumsheep]

Thanks for the help! And yeah i'm sure it's a 100fsb model with 28x mulitplier and maybe you couldn't find the 3230 as i bought it in the UK not the US (it's also out of production now) I think i'll consider joining the folding team, just want some more info on what you do first! And how much work it involves!

In reply to the other guy, yeah i realised after the post that i had been putting 125 : It's actually running 128 FSB.

Oh forgot, the memory is running at 166 mhz

 

[SidVicious]

It all boils down to knowing which chipset your motherboard is based on, beside, dual channel operation will require a pair of identical (ideally) memory modules.

 

[hacky_maximus]

dual-channel will boost your performance and so will do the PC4000 memory, runned in single channel .

 

[quantumsheep]

Oops forgot to say what my chipset is! Its an i845 socket 478 chipset, i don't tink it's dual channel

 

[SidVicious]

dual-channel will boost your performance and so will do the PC4000 memory, runned in single channel .

Again, it all depends on the motherboard's chipset, unless the chipset features a dual channel memory controller AND the appropriate CPU/MEM ratio to run the memory at 250MHz, getting a pair of PC-4000 modules would be like putting perfume on a pig, wasted bandwidth, wasted money.

 

[angry_ducky]

My Northwood currently at 3.6 ghz with 125 fsb is using pc2700 ram. Would getting some better ram (pc4000 or somethign similar) increase the perf of my cpu at all?

Any help would be much appreciated!

QuantumSheep

You overclocked an eMachines? I'm impressed. I assume you used ClockGen or the like, right?

 

[Scougs]

I'm pretty sure that the 845 doesn't support dual channel memory.

In that case, you would benefit from faster memroy. But, before you order any you need to find out what memory speeds are available in your bios.
It sounds like you are running with a 3:4 divider.

FSB - 128MHz*4=512MHz effective data rate
RAM - 171.7MHz*2=DDR341
Here PC2700 is fine obviously.

If you could raise it to 2:3 that would be an improvement.
RAM - 192MHz*2=DDR384
You might need PC3200 for this.

Best would be if you could set it to 1:2.
RAM - 256MHz*2=DDR512
You would need at least PC4000 for this.

I kind of doubt that you can set your motherboard to anything above 3:4 in which case you would not improve anything by upgrading to PC4000 RAM. You can always check your bios and see though.

 

[quantumsheep]

Thanks for all the help guys!. Im guna check my bios, see if i can change the divider.

If i can set it to 2:3 or 1:2 you know any good choices for some good value choices for pc4000 ram, as i'm not willing to spend THAT much on my budget pc.

 

[Scougs]

What would be a good choice would depend on how much you want and if you want to go with PC3200 or PC4000.

One idea might be to a 2GB kit for your Prescott system and move the 1GB to your Northwood system. If you don't mind waiting for a rebate you can get 2GB of OCZ EL memory for about $140.

http://www.newegg.com/Product/Product.asp?Item=N82E16820227210

 

[uber_g]

My Northwood currently at 3.6 ghz with 125 fsb is using pc2700 ram. Would getting some better ram (pc4000 or somethign similar) increase the perf of my cpu at all?

Any help would be much appreciated!

QuantumSheep

You overclocked an eMachines? I'm impressed. I assume you used ClockGen or the like, right?


uh on an Emachines ?


major Wtf-edge

 

[quantumsheep]

Yeah, but i got a REALLY good deal on it. November 2004 and i got it for £300 excl the 6600gt!!

 

[quantumsheep]

That sounds like a good deal! But unfortunalty i live in rip off Britain