I am feeling backpain and eye strain due to continuous sitting in frond of monitor.Now i am thinking of changing the chair. Could you post picture of your chair and about your backpain ...
Dont really get back pain. If I do start to feel a bit different then I just stand up for a few minutes and stretch. Might not be your chair... it could be posture. Someone I worked with got backpain because his resolution was too high on his monitor making him move closer to the screen and not sitting in an ideal position. He didnt realise he was moving too close to it... but it was doing something to his back.
I had backpains and changed my chair. But I also take more pause between my work and try to stretch now and then. My chair :