darkguset :
If it is indeed the fan i would do the following:
Try to check visually if something has dropped in there or touching the blades, or a screw is loose or something that makes the thing vibrate. If you find something and can clear it or a screw loose then go ahead and tighten it up.
If you can't see anything, DO NOT use a lubricating spray (WD40 or similar) as they usually do nothing to help a magnetic fan. Unless the fan has some bearings and they are rusted, which is probably 99% NOT the case. That is why i would avoid it.
You can try though to use some compressed air spray on to remove any trapped dust or foreign body. KEEP IN MIND: When using the air spray, use something like a pin or pen to immobilise the fan blades!!! If they spin too fast they could damage your motherboard irreversibly! You have been warned.
If nothing works, i would take it to a qualified technician to have it repaired, as laptops are very fidly things and even if you know what you are doing, the chances that you destroy something accidentaly are pretty high, not to mention the time that you will spend and the stress you will be getting while trying the operation.
Finally as mentioned before, do all this with the battery disconnected to avoid shorting anything.
Good luck!
One thing about the EX630 is, they fell under the 3 year warranty. Both of my EX630 notebooks have had heatsink fan problems. It's the Fan that starts out with a slight buzz sound. If you stand your notebook on it's side [screen open & system on], it would be standing on the left side [if you are looking at it from the front]. The noise should stop. That's how I checked mine. It can take anywhere from 3-12 months before the fan goes completely bad. My first one was actually hitting the fan casing, unless I stood it on end like I mentioned earlier. It's the bearings that go out.
On this model, you only need to take out 5 screws from the bottom to gain access to the entire heatsink/heatsink fan assembly. Then you have 7 screws to remove in order to take off the heatsink/fan assembly. The two sets of screws are marked- 1,2,3 & 1,2,3,4. That is the order that you need to follow when you remove & put your new/replacement assembly back on your system board. It takes about 15 minutes to remove & replace. Add a few minutes if you need to do some cleaning. The new one was improved a bit from the original one. Remember to clean off the heatsink paste off on the CPU & North-bridge & re apply paste prior to installing the replacement. I believe that the problem is a defective OEM part to begin with. I say that because the replacement is made a lot better than the original one.
One thing to think about is this. If you purchased your MSI EX630 with the Turion 2GHz/1MB/800MHz Processor, it might be a good time to upgrade the processor. I did, I went from the OEM 2GHz to the Turion II Ultra 2.3GHz/2MB L2cache/800/1800MHz HT Processor for $65.00. Gaining the extra 300MHz plus another 1MB of L2cache on the upgrade really helped. I think the temp stayed the same. I use a Infrared Thermometer gun to check the temp, it's better than a gadget on the desktop or a program & I just turn it on, check out the temp & I'm ready to use it on any other repairs I do. In fact, when I do work for people, I usually add the test result to the bill so they can see that I've went over & above what they needed fixed. Most people like the fact that I did check out the temp of their Processor for free & have the temps from different times-[idle, under load.]