need help for blank screen problem & can't enter bios

[kpsia118]

my spec:

GA-Z77P-D3 M.BOARD
INTEL i5-3570K
GT240 VGA CARD
8GB DDR3 1600 RAM
HUNTKEY 450W POWER SUPPLY
win7 sp1 64bit

now my problem:

last night i turn on my pc,all work fine...no problem
but i go to sleep...& after few hour...my pc in sleep mode
& i move my mouse & hit the keyboard...it still sleep,so i reset the pc...restart the pc
i can see the loading logo,but blank sceen after that...i sure window should be ok,i heard the window startup sound.

so i :

1)go in save mode unistall the vga driver,restart....then window loading fine all working
2)then i reinstall nvidia vga driver last version 314,window loading fine,but screen blank...,i heard the window startup sound.
3)i try enter bios,i restart pc press DEL key,& i saw black screen...i can't access bios

so any one help me here...

[ysw]

the system may not detect your graphics card.
1. plug your monitor to onboard VGA.
 or
2. move your graphics card to another PCIE slot to check.

[bigbite]

You could have a screen who fails !
It got warm when you where using your Pc then cool off when "asleep" and since then, it wont light up again.
I got once that problem. No one would expect a screen to f*** up that way but it does.

[kpsia118]

problem solved.

its monitor problem...new PC but very old monitor,that why...about 7~8 years old LCD minitor
should be capacitor problem.

i changed a new monitor,bios test ok,& windows tested ok...