I have several diffrent model computers however when I plug up a Dell D60 laptop I get the PXE-E53 error code. If I use the same cable and plug up a diffrent computer I can get the pxe menu. The interesting thing is that if I look at my devices in the management comsole. I see the mac address listed without an IP address. I can boot the device with a WindowsPE USB key and get an IP address so I know that networking/DHCP works. I have removed and redeployed the PXE service on the PXE relay workstation. I am out of ideas. The really wierd thing is that I know that last week I had the same issue and tried it on a D60 but then on the 11th try it worked fine. I dont think it is any kind of driver issue.
Dell had some bios issues with some models and PXE.
Update your bios.
I forgot to add that in my troubleshooting steps. It is now updated to the latest version of the BIOS. I get the same result. Thanks
Try removing 2 entries from your Pxe menu. Remember which ones so you can put them back.
Also if your entry for the D60 is long rename it to a shorter name, 12 characters or less.