Duron w/ Nforce

[xazos79]

Is it possible to have DDR-Ram with an Nforce Duron combo?
Would the fsb be at 100mhz or 133mhz?

Cheers All!

 

[oncleboris]

Sure, but unless you unlock your Duron L1 bridges you will probably be stuck at 100 MHz (if you're lucky, however, you could get a 10x100 to work at 10x133.

By learning the teachings of Zerthimon I have become stronger.

 

[xazos79]

If i don't want to fiddle with the processor, is it still worth it to have DDR at 200 instead of 266? And more importantly will pc2100 work at 100mhz?

 

[xazos79]

Oh another question i forgot. Do Nforce boards support pc133 sdram??

 

[Crashman]

nForce boards use DDR SDRAM. You can use PC1600 (DDR200), PC2100 (DDR266), PC2400(DDR 300), or PC2700 (DDR333). Any memory can run slower than its max speed. If you want to get the benefit of dual-channel DDR, you'll need two modules.

What's the frequency, Kenneth?

 

[phsstpok]

Crash, there's another thread discussing the merit of nForce dual channel (sorry I can't find the link). I was wondering what your thoughts on this are.

Basically, dual channel theoretically doubles DDR performance. However, memory is just a subsystem and thruput can't exced the FSB limitations. If FSB is set to 133 mhz then FSB bandwidth would be 8 Bytes * 133 mhz * 2 (for DDR) or 2133 MB/sec. This being the case it seems to me that the bandwidth of 4267 MB/sec for dual channel would just be overkill.

Now it's obvious that dual channel is needed when onboard video is used (because the video uses a lot of the bandwidth). However, when onboard video isn't used dual channel (or 2 DIMMs) aren't necessary because one DIMM can support just as much bandwidth as the FSB can handle. At least that's my impression.

As side note (also part of the other thread) the question of whether nForce supports asynchronous memory operation, specifically if memory slower than FSB is supported was discussed. Using the same example, if FSB was at 133mhz but memory was clocked at 100 mhz, it seems that nForce would work well, at least without onboard video. With two DIMMs the Dual channel bandwidth would now be down to 3200MB/sec. This is still well above the above the capability of the bus.

I don't know if it is an option on an nForce board but the ability to get high performance from low performance memory (PC1600) seems very attractive. It would also scale. How about a 200 mhz bus (400 DDR) with only PC1600 memory? You just need 2 DIMMS.

What are your thoughts? Does this sound reasonable.

<b>I have so many cookies I now have a FAT problem!</b><P ID="edit"><FONT SIZE=-1><EM>Edited by phsstpok on 03/25/02 04:41 PM.</EM></FONT></P>

 

[Crashman]

Dual Channel gives a little better performance, like 2%, I don't know why, but it does. Now if the Athlon went to 200MHz FSB, with a 100MHz FSB system bus, running dual channel, both busses DDR, you would have DDR400/64-bit connected to DDR200/128-bit, for matched bandwidth and excellent results. I've been pushing for a dual channel DDR chipset for Intel motherboards forever, but to no avail.

What's the frequency, Kenneth?

 

[phsstpok]

You lost me! Maybe I have my facts mixed up. I'll ask straight up.

What is the bandwidth of FSB for an Athlon 133(266)?
What is the bandwidth of single channel DDR at 133mhz?
What is the bandwidth of dual channel DDR at 133mhz? 100mhz?




<b>I have so many cookies I now have a FAT problem!</b>

 

[Crashman]

Athlon 133 (DDR266) matches evenly with PC2100 (DDR266). Dual channel PC1600 (DDR200x2) matches evenly with an Athlon at 200MHz (DDR400) because it's dual channel. It also matches the bandwidth of the stock P4, which is why I push for Dual Channel DDR for the P4. I don't think the nForce can run its memory at a slower async. rate than the CPU to take advantage of dual channel (for example, overclocking an XP to DDR400 while maintaining the memory at DDR200xDual Channel). But it would be cool if it could.

What's the frequency, Kenneth?

 

[phsstpok]

Sorry, must have been a brain fart. I thought I had it right the first time but somehow your first message sounded like a contradiction.

I kind of figured nForce wouldn't work with memory clocked slower than FSB. I just was hoping, hoping it could do something (anything) better than the other chipsets. That would be so cool to be able to overclock with low speed, low cost memory.

As for P4 Dual Channel DDR, d*mn Rambus deals.

<b>I have so many cookies I now have a FAT problem!</b>