Can a bad CPU cause that monitor does not connect?

[fruncfurt]

I've recently started to play around again in my old computer and everytime I start it up I get 3/4 very long beeps I've changed the ram ive also tried to clean the ram ive tried 3 diffrent video cards but nothing.
until I decided to change the cpu then the computer starts normally but monitor still won't connect Is it the CPU or the motherboard?

pc specs:
motherboard foxconn
Intel pentium 4 3.2 GHz
nVIDIA 512 MB
512 MB ram ddr400

 

[Tmagic650]

It is the motherboard

 

[fruncfurt]

Thanks

ok thanks for the reply tmagic Ima borrow a motherboard from a friend and see what happens.