Help with Nvidia EN8500GT Silent with games

Hello i just want some advice with the EN8500GT 256 version.I had a really bad problem with it and my cooler broke living me only with the heatsink passive which just isnt enougth for the silent version.So im gonna underclock the card:shader clock will be the same as on the stock clock on the orinignal(from 1100 mhz to 700 or 800 i will see),core clock to default original clocks not to the silent version but factory clock of 450 mhz,memory also.Im gonna use the 174.19 drivers,OS windows xp service pack 2(down from windows 7 ultimate with aero theme always on),also gonna use directx 9.0c so that i can run crysis on low but not gonna use the directx 10.So my card in windows 7 at normal was like 80C now i think it will be like 50-60 on normal and 60-80 in game since i will only is for League of Legends which needs shader 2.0 to run and 128 mb of ram so i will run it on lowest settings and resolution and do you think i will be able to get at least 40 fps and Wow on 50 fps on lowest(i can run it with 30 fps on intel gma 3150 so i guess yes But not shir reply to that pls)
My other spces:
amd x2 4000+ dual core 2.1 ghz
3 gb of ram ddr2
400W Crosshair high quality PSU
AND DONT SUGEST BUYING A NEW CARD SINCE I DONT HAVE MONEY AND I GOT THIS VIDEO CARD FOR FREE FROM MY FRIEND

Reply as soon and as much as you can i want to the mose thoughts i can thx in andvance <3 toms hardware pros