It sometimes helps to make a quick Airflow diagram on a piece of scrap paper. People have been known to reverse fans so check for direction and cleanliness of the blades.

Fans to pull air in are largely excessive - a clear air input passage is more important.

Usual setup:

Air in at bottom front.

Air expelled through PSU at Top Rear.

Too many holes makes for no draft - most inefficient.

If it ran ok with the side off that suggests that there is not a good circulation of air through the case.Check all the case vents are clear...take the front panel off and check there--the main cool air entry should be at the front lower end of the case and it's often difficult to check that area.Also look to ensure that the IDE ribbon cables and other cables are not getting in the way of the air flow through the case or obscuring the memory sticks.If there is no exhaust fan fitted at the back of the case consider fitting one if possible and make sure that the power supply fan is running.

It would be a good idea to remove and reseat the memory and any pci/graphics cards and all the cables to make sure there is a good clean connection in all cases.

so it maynot be overheating problem

after memory, you can check HDD use manufactur's diagnostic software

also consider bios upgrade if you can find new bios from manufacturer's website

See click here

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"Thus far, only Abit has come forward and stated that its capacitors have been faulty, although it is widely believed that many other motherboard manufacturers have purchased capacitors from the same component manufacturers as Abit. IBM admitted to using some of the Abit motherboards in its PCs." and

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