Sis pag pinasa mo ung passport mo make sure na mag attach ka ng letter kung bakit wala dun ung PC mo from Singapore and also follow up with an email. Kasi my guess is they gave 45 days to submit your documents and because you have to order your PC, most likely you will pass the 45 days alloted time that you were given to provide them with all documents.
Sending them a note and a follow up email will help your case sis so that they can extend the 45 days that was given.
It's important you do this sis para they know that you are trying to gather everything. Also, they may follow up with Singapore embassy that you did request the PC before they extend the 45 days so make sure na nirequest mo ung document.
I hope this helps you
Congratulations sis!!!!