UPS Prob or MoBo Prob?

[Techn0crat]

I have just assembled a PC for friend of my cousin with following specs.
CPU-C2D E7500(2.93 GHz)
MoBo-Gigabyte GA-G31M-ES2L
RAM-Kingston 2GB 800MHz
HDD-Seagate 250GB
DVD-WR-Samsung Writemaster
PSU-VIP 400 Watt(Silver)
Monitor-Dell 19"
UPS-Powercom (Forgot Madel No but something like 606A,have to press button for 3 second to turn on)
I assembled PC at her home and hoping everything should be fine I turned on PC.But it was beeping continuously.I checked Gigiabyte manual to find it may be power error.And Powercom manual says it should be charged for 16 hours for first time.I told them that I will come tomorrow to install ugh... OS..ugh..,they should keep UPS charging.I am sure that I connected all those small front panel wires correctly.
Is it UPS problem or anything else?It is my first time work outside my friend circle,so please help.
Thanks.

 

[Krow]

Without UPS does it boot?

 

[desiibond]

also, which cabinet are you assembling the rig on?
have you connected the power for CPU (four pin square molex next to cpu socket)?
beeps are coming from UPS or are they coming from cabinet's speaker?

 

[Techn0crat]

I didn't tried without UPS.
And beeps are coming from cabinet.& manual says Power error for continous beeps.Cabinet is Circle.