Valve’s much-anticipated Steam Controller went on sale on Monday, May 4, and quickly sold out amid what many consider a chaotic launch. Payment processing errors at checkout prevented many customers from buying the controller before it went out of stock (which occurred in minutes), leaving frustrated players empty-handed. Valve has acknowledged this rough start and is going back to the drawing board to ensure the next wave of orders goes more smoothly.  In a Steam post , Valve announced it will open a reservation queue for the Steam Controller tomorrow, May 8, starting at 10 a.m. PT/1 p.m. ET. Once you reserve your controller (limited to 1 per customer), your place in line will be saved.  When the controller comes back in stock, order emails will be sent in the same order that reservations were made.  Once your order email arrives, it will state that you have three days (72 hours) to complete your purchase, or you will lose your reserved controller.…