The information below has been extracted from an undated publicity leaflet from Dell/Wyse that is missing the usual dated copyright marking. A quick check with Google found mention of the D class mid-range Cloud Client family being launched in August 2012. The leaflet mentions:
"The range features dual core processors throughout with the D90D7 for Windows Embedded Standard 7, the D90DW for Windows Embedded Standard 2009, the D50D for Dell Wyse-enhanced SUSE Linux and the D00D for Dell Wyse WSM."
Another undated leaflet adds a D90Q7 to the line up - with a quad core processor.
The D-class is styled in a similar way to the Z class, but it is smaller than the Z class and also consumes less power - typically under 9 watts rather than under 15 watts.
The class may also be referred to as the 5000 series. I have a D10DP manufactured in October 2013 which carries the part number 909648-02L. According to a Wyse EOL document this part number is currently active (as of March 2017) and is for a 5010 with PCoIP (D10P) and comes with 8GB flash / 2GB RAM but a note says 'Flash Memory Upgrade Announcement 7/16/2015' which probably explains why mine only has 2GB of flash fitted. Another Wyse document implies that this was originally known as 5012-D10DP and is now known by the name Wyse 5010 thin client with PCoIP. Whatever it was known as there is no indication of 5010 or 5012 on the label - just the part number and Prod ID: D10P
When I first discovered the trailing P for PCoIP I wondered what might be coming as, up to now, all PCoIP thin clients I have seen have been based on a dedicated chip from Teradici. Luckily this not the case here as the D10P runs Wyse Thin OS with support for PCoIP.
Processors AMD G-Series dual core T48E 1.4GHz with AMD RadeonTM HD 6250 graphics
Quad core AMD G-Series SOC 1.5GHz with integrated Radeon HD 8000 graphicsMemory
D50D 2GB Flash / 2GB DDR3 RAM SSD storage also supported D90DW 2GB Flash / 2GB DDR3 RAM; SSD storage also supported D90D7 &D90Q7 4GB Flash / 2GB DDR3 RAM; SSD storage also supported D00D 0GB Flash / 2GB DDR3 RAM; SSD storage also supported Expandable up to 16GB Flash / 4GB DDR3 RAM / SSD storage also supported I/O peripheral support One DisplayPort. (Optional DisplayPort to DVI-I adapter available)
One DVI-I port. DVI to VGA (DB-15) adapter included
Four external USB 2.0 ports (2 front; 2 back)
D90Q7: Four USB 2.0 ports and two USB 3.0 ports
Serial and parallel connectivity supported through USB 2.0 adapters
Enhanced USB keyboard with Windows Keys (104 keys) and PS/2 mouse port. PS/2 optical mouse included.Networking 10/100/1000 Base-T Gigabit ethernet
RJ45 or SFP module
Factory options: Single and dual Band 802.11 a/b/g/n integrated wireless with external dual antenna
SFP module support for Fiber NIC network connectivity
Bluetooth connectivityDisplay VESA monitor support with Display Data Control (DDC) for automatic setting of resolution and refresh rate
DisplayPort: 2560x1600@32bpp
DVI-I: 1920x1200@32bpp
Dual display: 1920x1200@32bppAudio Composite audio jack: 1/8-inch mini, 16-bit stereo.
Internal mono speaker.Physical Height: 6.7 inches (170mm)
Width: 1.6 inches (40mm)
Depth: 7.3 inches (185mm)Power Average power usage with device connected to 1 keyboard with 1 PS/2 mouse and 1 monitor: Under 9 Watts.
The above are the specifications close to launch. It looks like things have changed a little since then in that the size of the flash drive has been increased.
The examples I've seen are the D10DP (5010) and the D90Q8 (5020)