I was able to install iAtkos 10.5.4 successfully and update to 10.5.5 with the help of this forum, especially Mysticus C* and Verdant.
I had to remove by second 8800GTX and my X-Fi soundcard but I was able to get my 8800 GTX, onboard sound and onboard nic to work nicely. I also have to boot with -v cpus=1 to disable one of my Intel C2D E6850 cores.

My main question is if anyone could share some insight on how I could use both cores and still be able to use OSX as it just crashes on me.

Also, I've run Software update and see some security updates as well as other software updates, one for Safari for example, I installed the nforce Core EFI kernel when I first ran the install, will using software update break my install ?

I did some reading about only running patched updates, however I read about being able to use software update normally with EFI ?

Thanks for any info you can provide,

JG

I finally got both cores to work and not have OSX freeze on me.

I removed the following files from /System/Library/Extensions/

AppleCPUThermo.kext
AppleFan.kext
AppleIntelCPUPowerManagement.kext
AppleThermal.kext

Rebooted and I was able to boot up normally, been up and running rock stable for about 4 hours now even with cpu intensive tasks.

So back to my other question, would installing security updates/itunes/quicktime updates using software updater break my install ?

Just a heads up,

I took the plunge and decided to download/install all updates in software update and I was able to boot back into OSX without issues.

Looks like I spoke too soon, now during cpu intensive tasks such as viewing 1080p hd movies the movie will stutter and mouse/keyboard will STOP responding. This is only when using both cores. =/

jgriff,

What kind of freezes are you having.... because im having the same issue. Its pretty intermittent and I was having trouble pinpointing the problem at all. I am running a quad core system with all cores active and I get about 30 min out of her before crash city

Noncentz

jgriff,

What kind of freezes are you having.... because im having the same issue. Its pretty intermittent and I was having trouble pinpointing the problem at all. I am running a quad core system with all cores active and I get about 30 min out of her before crash city

Noncentz

here are some scenarious of issues I have when I have all cores (2) enabled:

1. if I play an hi def movie, after say 15-30 mins the movie will just start stuttering and I can't do anything but reboot
2. playing mp3s and browsing the web, my USB mouse and keyboard will stop working (re-plugging them back in doesn't do anything)
3. I was extracting a large compressed file and OSX became unresponsive, I could do nothing but reboot.
4. I had left my computer turned on overnight and in the morning my screensaver was running but the USB mouse and keyboard were unresponsive and I had to reboot

I am at my wit's end, when booting with cpus=1 to run only 1 core, OSX is extremely stable... I can't even crash it even if I tried and boy did I try. This is the only thing standing in the way of my system being fully working.

If you've come across anything please do share =)

I am going to try another distro of OSX on my other drive and see if I'll have any luck with that.

Take care,

jgriff

EDIT: I'd like to add that while running completely stable on 1 core, I have my Intel Core 2 Duo E6850 overclocked from 3GHz to 3.6GHz (1600 FSB) ... are there any 780i owners have OSX running 100% stable without booting with CPUS=1 ?

Alright well I believe everything is in order. Finally got both cores working and haven't had any issues for several hours now. Did some large file transfers across HDDs and ran some 1080p movies as well with no trouble. I'm still over-clocked at 3.6GHz (1600FSB)

Here what I did:

I installed OSX using iAtkos v4.1i 10.5.4 (booted with nforce -v cpus=1 maxmem=2048)
But this time instead of selecting Kernel 9.2.0 nForce Core EFI, I selected Kernel 9.2.0 nForce SSE3 Non-EFI
Rest of the options I selected were: Chameleon Bootloader, Software Update Enabler, Remove Thermal kexts and nForce SATA

Installed just fine, I went ahead and did the 10.5.5 Combo update (used Mysticus C*'s nForce drivers/update and 4b. SPECIAL --nFORCE CHIPSET-- USERS steps found here: http://forum.insanelymac.com/index.php?showtopic=109102 )

All went well except System Profiler was giving me the message System Profile failed to identify hardware and Restart would not work correctly.
Using Kext Helper b7 from http://cheetha.net/ I installed AppleSMBIOS.kext (Version 1.0.14) I got from pc_efi_v80
After doing so, my hardware was recognized correctly, restart working fine and I've had no further issues. I'll post if this changes =)

Nevermind =(

Was watching a hi def movie and it just started stuttering and would not stop (USB mouse and keyboard would not work either, LEDs to the keyboard and mouse were on still though)
Just now I rebooted and left the PC for about 5 minutes and came back to find the mouse and keyboard just stopped working.

Back to using 1 core (CPUS=1).

Thanks for Verdant, I finally found the problem and solved it.

It was being caused by me using the onboardLAN, after switching to the Netgear GA311 NIC, it's been smooth sailing for more than a day now.