Problems with computer

[Kerotan]

I recently just bought some new hardware to make my computer better and i am having problem's with it =[

When i turn the computer on i get no response on the monitor, It just stays on a black screen, the monitor is plugged in because there's a green light on it and it is connected to the computer.

The new stuff i got are:
Geforce 6600 GT - PCI-E
K8 Triton Series GA-K8NF-9
AMD Athalon 64 3200
Some random make of ram from computer shop >.< (1gig)
Arctic Cooling T1 Silentium Silent Midi Tower Case - 350W Seasonic Silent PSU (CA-000-AR)

Anyone know what i can do to fix this?

 

[H4x3r]

did you get a new power supply? if not it could be that it is not providing enough power

 

[Kerotan]

Ah forgot to mention that...
I got a new case so it has a new PSU and such..

Arctic Cooling T1 Silentium Silent Midi Tower Case - 350W Seasonic Silent PSU (CA-000-AR)

 

[H4x3r]

350w isn't that much....also is the square cpu power connector plugged in and the same for the 6600gt?

 

[Kerotan]

Yes the square plug is plugged in.

Is there meant to be one plugged into the gfx card? I cant see any slot or anything for it >.<

 

[H4x3r]

whoopes thinking of 7800 anyway...check the PSU and make sure it's not on 225v..it needs to be on 115v.

 

[Kerotan]

How do i check it?
And if it is wrong how do i change it?

 

[H4x3r]

there should be a little red switch on the back of the psu...near the output cords...and it should either read 115v or 225v

 

[Kerotan]

Hmm i cant get access to the PSU because it has like a case covering it... (This computer case relly does suck >.<)
Ill try and get into it...

 

[Kerotan]

Ok i got the PSU out (Finnaly) and couldnt find a red switch >.<