I recently gave my trusty old PowerMac 7300 new guts, by buying a 1GHz
Powerlogix G3 cpu upgrade. That CPU is a 1GHz IBM PPC 750FX, with 1MB
level2 cache running at 1:1. (got it at OWC)

It did give the 7300 an incredible speed bost (judging by some testing
I did under Mac OS 9 and Linux)

I managed to get NetBD 2.0.2 running on it (2.0.2 ISO is not bootable
on OF 1.0.5 machines at the moment). To do that, I had to burn an
ISO-9660 CD-R with the 2.0.2 install kernel and the ofwboot.xcf file,
and then boot scsi-int/sd@3:,\OFWBOOT.XCF NETBSD.GZ. That worked fine,
thankfully. (It's really the only way to go on those machines, boot
floppies NEVER worked in my experience, and its much easier than doing
a netboot.)

Noticing the level2 cache wouldn't activate, I came upon posts about L2CR..

I managed to make my own config and put it in my kernel :
options=09L2CR_CONFIG=3D"(L2SIZ_1M|L2CLK_10|L2RAM_PIPELINE_BURST)"

This worked fine, as I now get this :

cpu0 at mainbus0: 750 (Revision 2.3), ID 0 (primary)
cpu0: HID0 8290c0a4<EMCP,ECLK,DOZE,DPM,ICE,DCE,SGE,BTIC,BHT>
cpu0: 500.00 MHz, no-parity 1MB WB L2 cache (PB SRAM) at 1:1 ratio

instead of just :

cpu0 at mainbus0: 750 (Revision 2.3), ID 0 (primary)
cpu0: HID0 8290c0a4<EMCP,ECLK,DOZE,DPM,ICE,DCE,SGE,BTIC,BHT>
cpu0: 500.00 MHz


Now, my question is, how do I make the processor run at its rated 1GHz
speed, instead of 500mhz? In Mac OS, it defaults to 500mhz, unless I
use Powerlogix' CPU Director to set it to 1000mhz.

I noticed that when trying linux on it, using BootX, it would get the
speed set by the CPU Director software. If I booted without the
extensions, and didn't set the CPU speed, and then boot in linux using
BootX, i'd get about 994 bogomips. If i let the extensions load
(therefore loading my 1ghz setting), and then boot linux with BootX,
I'd get around 1998 bogomips.

A little sorting benchmark showed me that it was really twice as fast
if I had the correct speed set under mac os prior to loading linux.

So back to my question, is there a way to get my processor running at
the speed it was made for?

Best Regards,

Francis Koclas