Here's what an Acer spokesperson told Windows Central:
"Sales will go live on 7/29 and we'll begin shipping the first week of August."
It would appear that HP and Dell will be the consumer's best bet for buying a PC with Windows 10 out of the box and first out the gate. Both have already started the pre-order process and, but HP will begin shipments on July 28, with next-day deliveries arriving on Windows 10's launch date on July 29. Dell will begin their shipments on that date, with the first PCs arriving to customers the next day on July 30.
Acer will begin selling a budget-friendly Windows 10 notebook, the Aspire One CloudBook, sometime in mid-August, with prices beginning at $169. Hardware details for the notebook have yet to be revealed.