Upgrading GPU on Toshiba Tecra M5

[Xplodzion]

Hi guys, I managed to get a Tecra M5 off ebay not long ago, upgraded the cpu from a T2400 all the way to a T5800 and the ram from 1gb to 4gb all for just £30, now I'm looking to upgrade the GPU, as it is limiting the laptop from becoming a decent portable gamer, it uses nVidia Quadro NVS 110 128mb which is equivalent to a 7300gs from what i gathered. but I'm not sure if it can be replaced or if its integrated, can anyone shine light on this? I mostly want to upgrade it because the severe lack of VRAM is causing performance issues in even the most basic games right now, thanks

If it can be upgraded can anyone recommend the kind of gpu i should lookout for? i'm not bothered if its not that much better performance wise, i just want something with at least 256mb of vram, preferably 512mb