I got to study Frame Buffer System of Linux 2.6.8 kernel so that i understand Linux Display System.
I am kindaa trying to find the kernel functions which are actually resposible for drawing on the screen....

So i compiled the option thru make menuconfig
Device Drivers-------------> Graphics Support ----------> Virtual Frame Buffer Support.

The description of the same is

This is a `virtual' frame buffer device. It operates on a chunk of │
│ unswappable kernel memory instead of on the memory of a graphics │
│ board. This means you cannot see any output sent to this frame │
│ buffer device, while it does consume precious memory. The main use │
│ of this frame buffer device is testing and debugging the frame │
│ buffer subsystem. Do NOT enable it for normal systems! To protect │
│ the innocent, it has to be enabled explicitly at boot time using the │
│ kernel option `video=vfb:'.

and when i give video=vfb: as boot parameters, it gets stuck after
mapping physical ram
v.i.z
the last messages diplayed, while booting are
0MB HIGHMEM available
511MB LOWMEM available
found SMP MP-table at 000faa60
DMI 2.3 present.
ACPI: RSDP (v000 COMPAQ ) @ 0x000e9e10
ACPI: RSDT (v001 COMPAQ CPQ0064 0x20040115 0x0000000) @0x000e5640

and it stays there for some time... 2-3 minutes and then i get the X Server running
Cntrl-Alt-F1 ........ shows the same above message.......
last being

By default i have boot param rhgb , which i deleted

As i am doing remote kernel debugging therefore when i add more boot params
gdb gdbttyS=0 gdbbaud=115200 along with video=vfb:
below are the last messages displayed....
0MB HIGHMEM available
511MB LOWMEM available
found SMP MP-table at 000faa60
DMI 2.3 present.
ACPI: RSDP (v000 COMPAQ ) @ 0x000e9e10

I also tried adding one more boot param
acpi=off
then the last message on the console is
0MB HIGHMEM available
511MB LOWMEM available
found SMP MP-table at 000faa60
DMI 2.3 present.
Intel MultiProcessor Specification v1.4

and when i don't add video=vfb: and instead use default boot params

i.e rhgb gdb gdbttyS=0 gdbbaud=115200

I get the remote debugging control
Waiting for connection from remote gdb ...
Though there is a message in (/var/log/messages)
vesafb: probe of vesafb0 failed with error -6
Its actually, vesafb returns -ENXIO ("No such device or
address")

any pointers/explanation on why and what is happening..

Your inputs would be very much appreciated...........