Yes, you can. Go to Akeeba Backup's Upload to Dropbox configuration and check the "Enable chunk upload" checkbox. You may want to change the Chunk Size below it to something smaller (probably 5 or less) if the upload fails. Please note that you'll also have to set the Part Size for Split Archives to 100Mb (larger files may fail to upload to Dropbox due to Dropbox API limitations).
As you can read in the documentation, enabling this option uses a new feature in the Dropbox API which allows us to send a big file to Dropbox in small chunks. Once all chunks are sent we ask Dropbox to "reassemble" the single, big file. We added support for this new Dropbox API feature exactly for cases like yours!
Nicholas K. Dionysopoulos
Lead Developer and Director
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