Check out the minimum system requirements for Battlefield 2142:
* 1.7 Ghz CPU
* 512 MB RAM
* 128 MB video card supporting 1.4 shaders (ATI Radeon 8500 / NVIDIA FX 5700 or above), DirectX Compliant
* Internet connection: 128kbit Cable/DSL connection
* Hard Drive space: 1.8Gb of space is required to install the game
* Windows XP with latest service pack installed DirectX 9.0c February 2006 edition (included) (does not work on Windows 2000/Me)
That was MINIMUM, which means it will JUST run it, the recommended is:
* 3.0 Ghz CPU
* 1.5 GB RAM
* 256 MB video card supporting 1.4 shaders (ATI Radeon X700 / NVIDIA GeForce 6600GT or above)
* Internet connection: 512Mb Cable/DSL connection
* Hard Drive space: 1.8Gb of space is required to install the game
* Windows XP with latest service pack installed DirectX 9.0c February 2006 edition (included) (does not work on Windows 2000/Me)
I very much doubt ANY PCI card can run the game plus your Celeron is just not built for gaming. Even if you have a Celeron D it would still lag. I have a 7900GT and a X6800 Core 2 Duo CPU, and at times it still lags at 1600X1200. You will have no hope of running Battlefield 2142 in low settings let along med with a PCI card.
I have yet to see a high performance PCI graphics card, I have only seen 9250s and 5200s, enlighten me if I'm wrong.