Auto shutdown broblem of mircomax X600, please solve the problem

1) What does the graphics card use for cooling? Passive or Fan?

If it is passive, and has no fan mounted to it, it is cooled with just a Heatsink attached to the GPU, (Graphics Processing Unit), and uses case cooling to cool it.

A) Heatsink; http://en.wikipedia.org/wiki/Heat_sink

The heatsink style used for a graphics card, does not stand as tall as a Heatsink used for a Processor.

B) GPU; http://en.wikipedia.org/wiki/GPU

If the Heatsink, and rest of the graphics card are covered in dust, etc, the GPU will overheat, and the graphics card will shut down.

2) Observe the age of the graphics card.
I just had an ATI Radeon X600X graphics card go out on me. It is at least 8 years old.

ATI made the GPU. The Radeon X600.
(It's AMD ATI now)

The Radeon X600 chipset is part of the Radeon R300 chipset series. (And also uses a PCI Express x16 connector),

http://en.wikipedia.org/wiki/Comparison_of_ATI_Graphics_Processing_Units#PCIe_.28X3xx.2C_X5xx.2C_X6xx.2C_X10xx

Actual exact code name of the GPU on your graphics card, is either the RV370, or RV380.
Looking at the chart, and using what graphics card you have, you can determine what chipset it is.

{ I'm also running a 22 inch wide screen monitor, and a 26 inch LCD HDTV for a monitor.
Dual monitors. Maybe that pushed the GPU over the edge }

For additional questions post in a Comment.

Regards,
joecoolvette