video card replacement, watt question

im usin a ati radeon 4350 512 MB. with a min. 300 watt requirement. but i have 250 watt psu o.O idk. Well i was thinking of upgrading to a 9600GT low profile (also 300 watt) card, would it work? and would it fit? i have a inspiron 537 slim....

also i had a 3650 in mind...

alright, ill stick with this, all i need is MW2 on LOWWWWWW then im good for another 3 years :). then ill get a new computer >.> with 3 years savings