Computer won't POST with new card

[sliptie]

I wanted to upgrade the graphics on my old rig for the kids to enjoy. When I press the power button, my led lights come on and the case, cpu, and gpu fans all spin. After about 5 seconds or so the gpu fans quit, with led lights and other fans continuing to operate normally. The monitor remains black and I receive no POST sound. I tested the card in a different rig and it worked fine. When I reinstall my old gpu, the old rig both POST and boots normally.

New graphics card:
GIGABYTE GeForce GTX 1050 DirectX 12 GV-N1050OC-2GD 2GB 128-Bit GDDR5 PCI Express 3.0 x16 ATX Video Card

Old rig and graphics:
OS: Win 7 Prof
Mobo: GA-78lmt-2sp Rev: 4.0 (upgraded to BIOS FDc 12/13/2012)
CPU: AMD FX-6100 3.3GHz
RAM: 2 x G.SKILL Ripjaws Series 4GB 240-Pin DDR3 SDRAM DDR3 1066 (PC3 8500)
GPU: HD 6770 850M 16B DDR5
Hard-drive: Samsung HD502HJ/ST500DM005 500GB 7200 RPM 16MB Cache
PSU: Antec earthwatts EA500 500W Continuous Power ATX12V v2.2 80 PLUS

What is my next step please?

 

[alceryes]

Did you disable the onboard graphics in BIOS?
Are you plugging the graphics cable into the onboard connector or the new card?

 

[sliptie]

Did you disable the onboard graphics in BIOS?
Are you plugging the graphics cable into the onboard connector or the new card?

I haven't disabled onboard graphics in BIOS. With the new card, I can't even get into BIOS.

The new graphics card has PCIe only. There aren't any other pins to plug something in. (forgive me if this doesn't answer the 2nd question, I may misunderstand what you meant or what else i'm supposed to do)

 

[alceryes]

Pull the card.
Hop into BIOS.
See what options you have for graphics.

The motherboard has 2 headers for graphics connection but it depends on whether you have a CPU with GPU - which you don't. Let's see what's in BIOS and go from there.

Also, check clearance for the card (make sure you're not hitting anything) and make sure it's plugged in all the way.

 

[sliptie]

Pull the card.
Hop into BIOS.
See what options you have for graphics.

The motherboard has 2 headers for graphics connection but it depends on whether you have a CPU with GPU - which you don't. Let's see what's in BIOS and go from there.

Also, check clearance for the card (make sure you're not hitting anything) and make sure it's plugged in all the way.

I went into BIOS :Advanced Settings: ICX Configuration:
under Internal Graphic Mode [UMA] is selected (UMA and Disable are the only options)
-when i disabled it and put the new graphics card in, I got a long series of beeps and the CPU wouldn't do anything.
-I cleared CMOS, installed the old graphics card, went BACK in BIOS and disabled it again. After doing this, windows booted up normally

*EDIT: clearance is good. New card has the same height as the old one

UPDATE: I've also tried a new PSU and had the same results.

 

[sliptie]

I replace my board with a GA-78lmt-USB3 R2 and everything works. I don't know if it's relevant, but my old board had only a 4 pin power connections. Either that wasn't enough for a PCIe powered graphics card, or the old board was just bad.