New PC beeps 3 times

[pradeep]

Hi, i have just built my 1st PC and some thing has gone wrong, i hear 3 beeps when i switch on the pc and nothing appears on the monitor, i have aso tried out of the case screwdriver test with just the basic components, ending with same results plz help:confused: and here is my pc config

Mobo -Intel DG33BU desktop board.
Processor - Intel core 2 Duo E6750 2.66Ghz 4MB L2 Cache, 1333Mhz FSB
RAM - Transcend 1GB x 2 240 pin JetRAM 800Mhz DDR2 DIMM latency 5-5-5 (JM800QLJ-1G MODEL NO. i guess)
Video Card - Nvidia Geforce 7600GT 256MB
HDD - Seagate 250GB 3GB/sec (16MB cache or something)
PSU - Zebronics ZEB-500W Platinum

[Cricket]

Are you sure all necessary power connectors are connected to the motherboard?

Do you have access to another compatible power supply? Never heard of Zebronics before and it doesn't sound like a high quality unit.

Do you have access to compatible RAM?

:) Cricket

[pradeep]

no i dont have compatible RAM or a PSU, all i have is an old DDR 512 MB RAM and a 300w PSU

[pradeep]

Is it a RAM and/or PSU problem?
when i switch on the PC all the fans work fine, the green LED on mobo turns on, and 3 beep sound is heard and thats it nothing on the monitor, does this mean that the PSU is working fine?

[Cricket]

Is it a RAM and/or PSU problem?Can't tell at this point.when i switch on the PC all the fans work fine, the green LED on mobo turns on, and 3 beep sound is heard and thats it nothing on the monitor, does this mean that the PSU is working fine?Nope, all that means is the power supply is sort of working. The power supply supplies several different voltage rails to the computer and one could be faulty while the others work fine. But if any of the rails are bad then you get problems like the one you're seeing.

To find out the cause of this problem you're going to have to substitute known working components with suspected problem components.

Might not even be the power supply or the RAM...could be your motherboard is DOA.

:) Cricket

[pradeep]

Cricket - Ok my pc jus started working now here's how

1. i removed the CMOS battery.
2. Switched the power supply on.
3. 3 beeps were heard.
4. Switched the power supply off.
5. Waited for 5 mins.
6. Inserted CMOS battery back in.
7. Switched the power supply on.

and that's it no more beeps, everthing is working fine...... any problems in future i will post here for advice.... Thankz for trying to help