Hi, I have a problem

I have a HP T120 for 2 years now. It was working good.  Till yesterday it has worked on wi-fi  all the time- no problems at all. Yesterday I did setup a lan connection between my PC and printers. After that I discovered that when I press ctrl – p or press print icon, my software lags for 10 second, then print window shows up (word, adobe pdf reader etc.) - I assume that pc is communicating with printer - status update etc. And the problem occurs only on lan, and when T120 printer is present, with wi-fi and T120 present it works fine (printing window pops in 1 sec). So I decided to erase the printer from my pc, and reinstall  fresh drivers form hp site and update the firmware in the printer. New drivers are called HP DesignJet T120 V4.

Now, everything works fine, print window shows up in 1 sec, but there is another problem - printer prints only 1/3 of the document e.g. if I want to print 297 x 420 (A3) - I will get  paper size 297 x 420 from the printer but only 1/3 of it will be printed - right side looking on the printer when it prints, and the rest will be blank.

If i go to control pannel - devices and printers - printer properties -> advanced and change the driver from new HP DesignJet T120 V4 to my old ones HP DesignJet T120 - it prints fine - whole page, but lags, as soon as I change then to new, it stops to lag, but doesn't print the whole page. So I think it is the drivers fault.

I kindly request a resolution for my problem - a) old drivers stays but lagging is resolved, b) new driver stays but printer prints the whole page.

For security reasons  and speed ench. I don't want to use wifi connection. I am a IT specialist so please don't post solutions: did you try on/off and I did read all the other solutions (rather lack of solutions) to this problem, as I am not the only one.