The Rdesktop version is too old. You will need to patch it. I would try to go to the most recent stable version. The last time I did this was before Neoware was bought by HP many years ago. I would bet that there is someone that has done it more recently. How many of these do you have? If you have less than about 10 I would consider new Thin Clients, although considering the specs of the T5545 they will do what you want with the correct software.
Hp T5730 Windows 7
You may want to look at this HP ThinPro Add-On (Brokers Update) :
Hp T5730 Drivers Windows 10
It is older than your version, but it might give you some insight to the problem.
Page 7 Option, drivers, and support are available directly from third party. Drivers must be installed. For a complete list of monitors compatible with HP Compaq thin clients, it is important to cross-reference the supported video resolutions of the HP Compaq thin client to the supported resolutions of the monitor. Go to the HP Consumer Support page and click the Drivers & Software tab. In the Search box, enter your product name/number (for example, Pavilion FM475EA or HP Pavilion dv71020eo), and then click Find my product. Re:Anyone have the schematic for the HP T5730 ThinClient, or pin-out for its PCIe 16x slot 2011/10/09 11:22:59 Thanks! I wish I could attach the PDF file, data sheet books for the chipset, but the forum software just supports pictures, and even then, no larger than 500kB. The PDF's are over 1.5 MB each.
Hp T5730 Spec
Go to the HP Consumer Support page and click the Drivers & Software tab. In the Search box, enter your product name/number (for example, Pavilion FM475EA or HP.