Microsoft rates the HP Officejet Pro X551dw at 70ppm, but the company also quotes an ISO speed of 42ppm. Even that is wishful, given our results, but the printer is certainly fast. The 5-page black text document took 19 seconds to print, giving a speed of 15.8ppm and, oddly, this was identical when the document was printed in draft mode.
The 20-page document increased the speed to 20.7ppm, still a way short of the rated speed, so we tried an 80-page document, composed of text, graphics and photo pages, and saw a speed of 29.5ppm. It would have been higher, if the printer hadn’t spent 34s preparing.
Preparation time doesn’t have to be included in ISO speed measurements, and more and more printer makers are taking advantage of this with sometimes extended periods of housekeeping happening before printing starts. Anybody waiting for a printed document, however, does have to endure this prep time as part of the print job.
A 20-side duplex document gave 17.1 sides per minute, which is very respectable and photos took 28s in best mode from a PC and 19s in normal mode from a USB drive plugged into the socket on the LCD display mount.
Despite the high speed at which this machine prints, the quality of the pages it produces is excellent, better than many conventional inkjets. Black text is near laser quality and colour graphics are vivid and solid. Photos are detailed and with a much wider range of colours than from any laser. You can also print on glossy photo paper, of course.
Using the highest yield consumables, which give the best page costs, we calculate a black page cost of 1.7p and a colour page cost of 5.0p. Both these are very low, a lot less expensive than the majority of either colour lasers or inkjet printers. This is perhaps the biggest single advantage of this machine, particularly when there’s no speed penalty.
The HP Officejet Pro X551dw really is a new concept in office printers and this machine is an excellent first offering. It’s very fast, very cheap to run and produces high quality black and colour print on both plain and photo paper. It’s reasonably expensive to buy, but not when compared with colour laser printers with anything like the same specifications.