Hi Stephen,
> > I have two exactly the same Athlon systems at 750MHz and 512 meg memory
> > (@ 133MHz). In the BIOS there is a option: "DRAM to CPU Frequency
> > Ratio", which can be 3:3 or 4:3. The Help says: "Using this item to set
> > the operating frequency of DRAM".
> >
> > I just installed Debian on the machines, rebooted, changed one machine
> > to 3:3, the other was 4:3, and compiled a kernel on both of them. The
> > time it took was almost exactly the same (about 5 min 32 sec). The 3:3
> > one was 0.24 seconds faster.
>
> It is likely there are other limiting factors.
Like? And should the faster ratio not make a little difference with a
kernel compile?
> > Does Linux ignore the DRAM to CPU Frequency Ratio (if at all possible),
> > is it just a useless BIOS option (because of hardware limits or
> > something), or is it not supposed to make the machine faster (if, what
> > _does_ it do then ;-) ? (the book that came with the machine doesn't
> > tell me much about the option).
>
> The question is what is the ratio between the speed of the CPU
> bus and the speed the DRAM should run at. 3:3 means same speed, 4:3 means
> the DRAM runs faster than the CPU. If you CPU runs at 100mhz for it's
> communication to the chipset and you use '3:3' then your memory also runs
> at 100mhz. If you use '4:3' then your memory runs at 133mhz while the
> CPU runs at 100mhz. etc, etc.
Oke, then I do understand the option. So if I have 133MHz capable
memory, the 4:3 ratio _should_ make a noticeable difference. But it
doesn't. Now I'm curious why. :-)
Thanx for your thoughts!
Ookhoi
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