I'm trying to upgrade my brother's graphics card for his birthday. He has an hp slimline s3120n and from doing some searching it seems like it is possible to upgrade it but it's not ideal. He currently plays warcraft 3 and World of Warcraft but it is really choppy and laggy at times. I read that he could upgrade but it would need to be a low profile card that requires no more than 160 watts of power? I'm not that computer literate so if someone could point me in the right direction of a graphics card that would fit in his computer and hopefully give it a little boost, that would be great. Thanks!