What are the hurtz for this?

60Hz refresh rate. This is fine for just everyday use, but not for gaming. for gaming you need a monitor with a greater refresh rate like 144hz. That way it will help show the fps that you're GPU puts out... (note) this monitor will still work for minor games that do not require a-lot from you're computer... but if you play the Crysis series on this or even Shooting games, and some racing. Then you will be greatly disappointed.

Hi what was the problem as it was refurbished? is there still a warranty/guarantee if anything does not work?

Hello, A refurbished item is an item that was originally sent back to the manufacturer for reported defect reasons. The item has been repaired to function properly and is now being resold at a discounted price. We can only guarantee what is listed on our Product Page. Newegg always offers a 30Day return period. Thank you, Newegg Support