Review of FSB speed

[wacki]

I have a computer that has this mobo

http://www.asus.com/products4.aspx?modelmenu=2&model=595&l1=3&l2=13&l3=0

the front side bus is a huge bottleneck right now. Everything else isn't even being mildly taxed.

How much faster is this:
http://www.asus.com/products4.aspx?modelmenu=2&model=744&l1=3&l2=15&l3=0

And what does 2000 / 1600 MT/s mean?

I'm so far behind on my comp stuff.

:-(

 

[Matthias99]

Those boards both use the same speed for their memory (DDR400). The A64s have a LOT more bandwidth between the CPU and NB, but this is hardly ever a 'bottleneck' for the system. What makes you think it's the FSB that is bottlenecking you?

And what does 2000 / 1600 MT/s mean?

That's the maximum speed of the HyperTransport link, in megatransfers/second (think it's a 16-bit transfer size). This is mostly irrelevant, as the A64 CPUs only have a 1000Mhz HT link.

 

[wacki]

What makes you think it's the FSB that is bottlenecking you?

I did a perfmon.exe and my pages/sec are maxed. The avg. dik queue length is being used but rarely maxed. The Processor rarely goes about 30% usage.

 

[wacki]

Those boards both use the same speed for their memory (DDR400). The A64s have a LOT more bandwidth between the CPU and NB, but this is hardly ever a 'bottleneck' for the system.

Same FSB speed but a lot more bandwidth? What did they do just use more channels?

Any good articles on this?

 

[Matthias99]

Originally posted by: wacki

Those boards both use the same speed for their memory (DDR400). The A64s have a LOT more bandwidth between the CPU and NB, but this is hardly ever a 'bottleneck' for the system.

Same FSB speed but a lot more bandwidth? What did they do just use more channels?

Any good articles on this?

Athlon64s don't actually have a 'front-side bus' like the P4 and AthlonXP; they have an onboard memory controller directly hooked to the CPU, and a dedicated HyperTransport link to the Northbridge chip. Many of the initial A64 preview/review articles talked about this in great detail.

Memory bandwidth is the same; Athlon64s use either single- or dual-channel DDR400 (single-channel on Socket754, and dual-channel on Socket939). Socket940 ("Socket M2"/"Socket AM2") is coming out next Spring and will use dual-channel DDR2.

I did a perfmon.exe and my pages/sec are maxed. The avg. dik queue length is being used but rarely maxed. The Processor rarely goes about 30% usage.

You never responded in your other thread (where I asked about your memory usage). If you're paging to virtual memory on disk, you will by FAR be limited by the speed of the drive rather than anything else (which is why your CPU is barely being used at all; it's just sitting and waiting for data from the disk). Stop the memory thrashing and your performance will improve. The FSB on your current system is not the limiting factor.