Why full speed Fan and loudly iMac 27 mid 2011

Hi Please I need Help !

long story , I took my Imac to apple care for replacing Video card because the vertical green line conman issue . then after they replace it , it work fine .

problem start when I try to upgrade HDD with New HDD .

I did replace the HDD then I finished reconnected all the cable of LCD. when I turn my Imac I smell something got burned !

I found out the connector (molex ) of the Display Port Power Cable got burned and also one small chip below the connector too .

so I disconnect all the cables of LCD, I did reattach the old Original Apple HDD , I contact my Imac Via TV by HDMI Cable , it work fine bootable I reached my desktop file . ! but the Fan work Loudly and full speed .

- I installed ( HDD Fan Control ) application it show , HDD 1024 PRM , ODD 3234 PRM , this app couldn't solve the problem or control the Fan I tried all option of app Auto, Manual, Smart .

- Idid SMC reset and PRAM reset nothing solve

a) my question first : is there hope to use LCD which option I must go with on this case :

1- got new Display Port Power Cable only !

2- replace the cable + connector (molex) + the small chip

3- replace the logic bored

B) my second question : I can live with Via Monitor rather than using LCD but

how I will solve the problem of full speed loudly fan !

I wonder if the burned chip could effect the logic board .

I did attach Photo on the Link below :

Notice : done SMC reset and PRAM reset nothing solve

Thank you for your time anything will be helpful