How to write a thank you letter for donation ( 四套電腦〉

Dear ______________,
I am writing to express my heartfelt gratitude to your donations of computers . With your donations , we benefited a lot .
Thank you very much . Your help helps us a lot .
Thanks again.
Yours sincerely ,
________________

Dear Sir
re: donation
We are writing to thank you for donation of computer. The 4 sets of computer have been received on (date of receive) and have installed in our entertainment room.
Best regards,
your name
your position
the name of center