I found a post elsewhere that has a lot of info
Here is a summary
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Now If know what the -f is, and seems like I can do the Graphics Mode as well in the boot parameters..
was getting tired of editing the chameleon file the whole time.
Darwin boot loader level flags, for Darwin version 8.0:
-v = verbose mode. Basically tells you wants happening during boot up.
-x = Safe mode. Basically boots your system with the bare minimum kexts.
-s = Single user mode. Command line only mode. Allows you to run commands as root to fix system.
-f = Tells the machine to reload all kext and dump the boot configuration cache, (kext cache found in: /System/Library/Extensions.mkext, you can delete it manually and the system will recreate it).
"Graphics Mode"= Tells the system what resolution width, height, color depth & refresh rate to boot the OS with.
Ex: "Graphics Mode"="1024x768x32" WIDTHxHEIGHTxDEPTH
For VESA 3.0 graphics, you may append a refresh rate after an "@" character
Ex: "Graphics Mode"="640x480x32@60" WIDTHxHEIGHTxDEPTH@REFRESHRATE
rd= This parameter state what is the boot disk to use (instead of using the boot menu appearing before the prompt) you state the drive and partition in here: diskXsY where X stands for the disk number (first disk, usually primary master in IDE or SATA) 0 second disk is 1 etc.) and Y stands for the partition on that disk starting with 1 as the first partition.
Ex: rd=disk0s1 If you have one disk and one partition the parameter will look like this.
You can also use rd=*<IODeviceTree path> for booting from a PCI RAID card for example. Ex: of this would be rd=*/PCI0@0/CHN0@0/@0:1
Platform= this parameter sets the platform to use at this boot time.
Examples of this flag are:
platform=ACPI (ACPI support)
platform=X86PC (non ACPI support)
platform=ACPI|86PC (try to support ACPI if fails do not support it)
?memory = this info screen display information about the memory on the machine
?video = this info screen display information about the video card supported graphic modes
ACPI Flags
acpi=off = Don't enable ACPI
acpi=ht = Use ACPI boot table parsing, but don't enable ACPI interpreter
acpi=force = Force ACPI on (currently not needed)
acpi=strict = Disable out of spec ACPI workarounds.
acpi_sci={edge,level,high,low} Set up ACPI SCI interrupt. EX: acpi_sci=edge
acpi=noirq = Don't route interrupts
Darwin flags most commonly added to com.apple.Boot.plist file:
Note: Any flag can be added to your boot.plist but these are just the common ones.
"Boot Graphics"=Yes = Yes or No. Use graphics mode or text mode when starting. Turns off vesa mode graphics at boot.
"Quiet Boot"=Yes = Yes or No. Use quiet boot mode (no messages or prompt). Same as adding -v option.
Timeout=3 = Any number 1-100. Number of seconds to pause at the boot prompt.
debug=0x144 When added as a boot flag to your com.apple.Boot.plist will give you details about a kernel panic you have at any time when running OSX. I believe it is the same as debug=0x100, not sure.
Unknown Darwin Boot Loader Flags
Text Mode = Might be the same as -v not sure.
Kernel Flags = ?
MKext Cache = Might be to specify the mkext cache to use. Not sure.
Kernel = To specify kernel to use. Correct?
Kernel Cache = Possibly to specify where the kernel should cache?
Boot Device = Might be the same as rd= above. Not sure.
boot-uuid = Believed to be the same as for example rd=disk1s1. Not sure exactly how this is formatted and if it has any other special characteristics. Might be useful to some where the rd flag gives you trouble.
CD-ROM Prompt = ?
CD-ROM Option Key = ?
-F = Not sure could be the same as lower case -f flag.
Kernel level flags:
-l = The flag attempts to enable the L2 cache if not already enabled. Not sure if this works on hacks. If your having an L2 cache issue try this flag.
cpus= Tells the kernel how many cores there are in place. Ex: cpus=1 OR cpus=2
idlehalt= Lets you set two values ether 1 or 0 stating true or false, if set to true then at idle time the cpu will halt causing power saving and cooling of CPU, if set to 0 then the cpu will allways run even in idle time.
idlehalt=0
idlehalt=1
cpuidle= Lets you set two values ether 1 or 0 stating true or false. This flag is exactly the same as the one above I believe. Please correct me if I'm wrong.
cpuidle=0
cpuidle=1
-legacy = causes the system to load in 32 bit mode while running on 64 bit version of OS X
debug=0x100 = To show information about kernel panics & other useful info from system at startup. If you are getting a auto rebooting from bad kernel or kext being loaded use this flag to see what it is. Will help when posting information on this forum for diagnoses.
maxmem=xxxx = This allows you to specify maximum memory used by the system. Not sure if the rest of the memory is used for apps or not. Many people have to use this if they have 4GB of memory in a 32bit OS. Ex: maxmem=2048