On Mon, 26 Jul 2004 22:24:47 -0400, Dennis E Strausser Jr wrote:
>
> "Wes Newell" <> wrote in message
> news
an.2004.07.25.06.16.33.892430@TAKEOUTverizon .net...
>> On Sun, 25 Jul 2004 00:28:51 -0400, Dennis E Strausser Jr wrote:
> <Snip>
> I e-mailed AMD to just find out which of us is right on
> the FSB thing.
You didn't have to do that. All you have to do is look at the data sheets.
I tried pinning AMD to wall a while back about why they erroniously use
the wrong speed of the FSB. Here's the reply.
------------------------------------------
Thanks for contacting AMD's Technical Service Center. The stated FSB
speed is the effective frequency. The physical frequency is half the
effective frequency - 100, 133, or 166MHz. Most motherboards will state
this physical frequency rather than the effective frequency.
The reason for this is that, in the past, chipsets would transfer data
once per clock cycle. With the introduction of the Athlon's chipset,
they began transferring data twice per clock cycle, effectively doubling
the amount of data transferred even though the physical frequency
remained constant. This is similar to DDR (Double Data Rate) Technology,
which is used in DDR SDRAM. You will also find similar technology used
in other products as well, such as RDRAM.
Hope this helps.
Best Regards,
Jeff Hanaoka
AMD Technical Service Center
Original Message Follows:
------------------------
You refer to the Athlon FSB speeds as 200mhz, 266mhz, and 333mhz. Is
this really the front side bus speed? I can't find a motherboard that
supports front side bus speeds higher than 166mhz. What gives?
------------------------------
> They are yet to get back to me.
> By this point, this thread is getting so big, I don't care
> which of us is right or wrong on it.
> I just want to know for sure.
>
> I might just e-mail Intel on this as well, I want to know why..
> When they say 800 (FSB) why they don't just say 200 fsb.
> and what the heck does this 200 x 4 help?
Well, DDR, QDR (as I call it) helps with data throughput, and marketing
types tlike big numbers, so they just play with them.
> Only thing I can think of is this.
>
> 200 x 2 = 400 CPU 1
> 200 x 2 = 400 CPU 2
> to a total of 800
> To make it act more like there's really 2 CPU's
> If there was no bottle neck, it would be like having 2 CPU's
>
> What do you think on this?
What? It's just data bandwidth. And to be honest, enough is enough. IOW's
as long as the bandwidth is there and the cpu doesn't have to wait on it,
these numbers don't mean crap.:-)
Now just try and use these false numbers when building an actual bus,
determining the correct multiplier, even determining the speed to set, and
the list goes on. Everyone knows the Athlon XP 3200+ has a muliplier of 11
and the default speed of the cpu is a real 2200MHz. Now how easy is it to
figure out the speed of the clock of the FSB? 2200/11=200, not 400. Bus
speed refers to clock rates. Data rates have a whole new meaning. See The
Real Front Side Bus in link below.
--
Abit KT7-Raid (KT133) Tbred B core CPU @2400MHz (24x100FSB)
http://mysite.verizon.net/res0exft/cpu.htm