I have been struggling(on and off) with debian for a long time, I ususally get stuck with making my network connection work, DHCP always fails. I got it working today, I needed to boot it with the kernel option "noapic". So I am guessing that must use a kernel that has certain features(apic) not enabled. Do you know what specific options are disabled using that boot parameter? I know I have had apic enabled in other kernels I have used on that computer in the past with no bad effects.

to some up my question: what makes the "noapic" kernel different?

Just a guess (that will annoy debian fans) debian is way behind the curve because of petty "free" battles (unless you offer your first-born along with your software, it might take a while to be adopted into the debian world, and god help you if you accept donations or other monies for your efforts, you get the idea). So, apic, while it isn't tops for any distro, Debian's policies (a "security" arrogance/ignorance) mean that their distro will take a few years before they get around to a reasonable apic usage.

In other words, if you want to use Linux, and don't have overarching hangups, just about any other distro is going to be a better choice. Sad thing is, it wasn't that long ago that the debian folks were setting the pace, and supporting debian was a no-brainer, because their proof was in their pudding.

As an alternative, you might use the apm options for power managment.

apart from the strange rant about debian
your motherboard has or doesn't have an apic controller that can be turned on or off in BIOS
it consists of three parts - a local APIC, an I/O APIC and an APIC bus.
it stands for
Advanced Programmable Interrupt Controller
apic is an intel cpu specification that uses writable cpu registers to distribute interupt handeling evenly accross multiple cpus by collecting the interupt signals from i/o devices and redirects these signals to local cpu specific APIC handlers via the APIC-bus

this is done entirely by the kernel and has nothing to do with "distro"
one would assume this has to do with what is supported by your motherboard and your BIOS settings

I tested it on Debian Weezy- noapic disable additional c api in kernel - so some signals to the processor and main line was incorrect. Effect - mine K8 processor worked as K7 and processor utilisation was bigest for specified PID and my sound card interrupts the sound in VLC Player permanently.

"nolapic" - disable kernal drivers for local apic - effect is full power of the first core (only one core is enabled) in mine amd K8 actual status was 4.2Ghz with noalpic and 1.4Ghz with lapic=on (but all cores was enabled).
I don`t know if mine processor have 1,4 Ghz per core/thread or 4,2 Ghz per core/thread. Sometimes Sound card interrupted also.

noapic:
sasza@sayoonara:~$ lscpu
Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Byte Order: Little Endian
CPU(s): 4
On-line CPU(s) list: 0-3
Thread(s) per core: 2
Core(s) per socket: 2
Socket(s): 1
NUMA node(s): 1
Vendor ID: AuthenticAMD
CPU family: 21
Model: 2
Stepping: 0
CPU MHz: 4200.000
BogoMIPS: 8381.98
Virtualization: AMD-V
L1d cache: 16K
L1i cache: 64K
L2 cache: 2048K
L3 cache: 8192K
NUMA node0 CPU(s): 0-3

nolapic:
sasza@sayoonara:~$ lscpu
Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Byte Order: Little Endian
CPU(s): 1
On-line CPU(s) list: 0
Thread(s) per core: 1
Core(s) per socket: 1
Socket(s): 1
NUMA node(s): 1
Vendor ID: AuthenticAMD
CPU family: 21
Model: 2
Stepping: 0
CPU MHz: 4200.000
BogoMIPS: 8379.89
Virtualization: AMD-V
L1d cache: 16K
L1i cache: 64K
L2 cache: 2048K
L3 cache: 8192K
NUMA node0 CPU(s): 0