Yeah, it's most likely a broken solder joint under the GPU where it links to the scaler chip. A common problem, send it back to MS if you're in warranty but if it's over a year old you're pretty much out of luck unless you decide to try to fix it yourself/send it to someone else to fix. It might work occasionally, but it sounds like it's leading up to an E74 error.
Before anyone suggests it, don't waste your time with the stupid towel trick.
On the other hand, if you got it going again by resetting display settings, it might not be a hardware issue at all. Result