I have a mh 721 bought less than 6 months ago from uscutter ebay (so out of 90 day warranty). I set it up (carpeted room) and it wasn't grounded to the post. I didn't even know that it needed grounding as it came with no wires. I was cutting for a new order couple of days ago and I noticed that the machine stopped cutting, with blank screen on the cutter lcd. I rebooted the machine and computer and from that point on the blade will not lift. I read almost all of the posts here regarding this topic and it seems like its static/zchip/motherboard issue. I did the 9V test to the carriage and blade will jump on contact with the battery. Also, it seems to cut the design (with the blade down the whole time) so I guess I can rule out that it's motherboard? I've leaned towards faulty/fried z axis chip and I just went ahead and ordered a new chip. I have to fill this order very soon. Can anybody help to narrow it down that it's z-chip issue? Should I just go ahead and order a new motherboard instead of z-chips?