wanting a graphics card for an Emachines pc

[ineedtoinstall]

I am currently surfing through the refurbished selection on NewEgg.com and just want to make sure what I purchase will fit so there's less hassle in life.

ECS 945G-M3 motherboard is what I am using and I am not sure which video cards I could use since this is an older motherboard, it's a prebuilt pc from Wal-mart which was given to me as a gift.
I want to expand the ram and include a video card as well, from what I've seen this pc can only run two 1 gig ddr2 ram sticks so that's easy to price.

http://support.gateway.com/s/MOTHERBD/Shared/4006188R/4006188Rsp2.shtml

There is a link with the motherboard information but I am not which video card would be compatible.

ASUS 8400GS-1GD3-SL GeForce 8400 GS 1GB 64-bit DDR3 PCI Express 2.0 x16 HDCP Ready Video Card
http://www.newegg.com/Product/Product.aspx?Item=N82E16814121720
I've been considering this since it's such a low price, I see the motherboard support is PCI Express x1 & x16 would that mean the express 2.0 is acceptable?

If you have a suggestion for a card which would work please let me know, also let me know if I am missing any information needed to make judgement.

Thanks for reading, Jason

 

[Madn3ss795]

You can use any pci-e x16 card on your machine as long as the PSU that came with your emachine can support it.

 

[ineedtoinstall]

Is there software to use to detect the PSU brand and power or do I just need to remove the shell and take a look inside?

 

[Madn3ss795]

You have to take a look inside.