Big problem, please help. Monitor no signal

Dear all big brothers,
I just bought a Visiontek x1650 Pro (256MB, PCI-E) vedio card. I installed it on the monther board. Initially, it worked well. However, after I rebooted the computer, the monitor said no signal.
I tried several times but same thing.
So I took off this vedio card, and plug the monitor into the on board vga socket, the monitor also said no signal. however, before this onboard vedio chip works well and I have used it for a year.

I do not know whether it is because their is some confliction or I burnt the motherboard accidentially.

Would any of the high hands give me some suggestion.
Thanks a lot.

The configuration of the computer

Motherboard
ASUS A8R-MX/SI 939 ATI Radeon Xpress 200 Micro ATX AMD Motherboard - OEM
http://www.newegg.com/Product/Product.aspx?Item=N82E16813131049

CPU
AMD Athlon 64 3400+ Venice 2.2GHz Socket 939 Single-Core Processor Model ADA3400DAA4BY - OEM
http://www.newegg.com/Product/Product.aspx?Item=N82E16819103023

vedio card recently bought
Visiontek x1650 Pro (256MB, PCI-E)
https://shop2.outpost.com/product/5164006?site=sr:SEARCH:MAIN_RSLT_PG