vaio vgn-nr420d - How can i tell if the fan is broken?

[frazelle09]

This is a pretty good laptop but my GKrell reading is over 150 degrees F.  Otherwise i can't really tell if the fan is working or not.  All i get is a very little hot air out the right hand vents.  Is this temp reading sufficient for me to assume that i need to get another fan?

Have a great evening! 

[pupthai]

My laptop I can see the fan from the intake on the bottom.  I can hear it run at higher speed if the load is high.  Does gkrell show high cpu use - I have seen programs in back ground run wild before.  Make sure the air intake is clear and didn't suck up a dust bunny.  could be it is just got air blocked.

[Just17]

I suggest opening it and cleaning out the heatsink ....  and even renewing the thermal paste if the unit has been running hot for a while.

[frazelle09]

Thanks, guys.  Those ideas sound within my capabilities.  i just went online to find out replacement fans run about $35 U.S. and are not as difficult to install as the little rear replacement power adapter was.

Gkrell does not show high CPU usage nor does the machine make more noise as it gets hotter.  Yesterday i did an update and while it was installing the packages, it went to 92 F - ug.

i've got to see if i can get thermal paste from my W-Mart, if not, then our local Radio Shack should have some.

i'll check it out and get back.  In the meanwhile - have a great morning! 

[horusfalcon]

Hi, frazelle09,

Just some random thoughts here about how I would proceed were I in your situation.

One thing you might try to do is place your ear close to the fan inlet port and start the laptop.  If you can hear the fan spin up when the laptop starts, it should be in good enough condition to operate normally.

I take it you have already tried blowing out the fan and heatsink with canned/compressed air?  If not, give that a go (and if using compressed air, be careful not to use too high a pressure on the air stream - about 20 psig is a good maximum, and even that may be too high in some cases.  Short bursts from a few inches back (i.e., not at "point-blank" range) until you get a feel for things is better).

Before you go ordering parts, it might be wise to have a look-see and figure out whether the fan or the heatsink thermal coupling (paste/pad/whatever) is the problem.  If you need to redo the paste, be aware that most laptop heatsinks are screwed down by screws that are numbered for the correct sequence of removal/reassembly.  (That is, loosen and tighten these screws in numerical order.)

You may already know this, but if phase change material was used previously on the heatsink, the CPU die may become bonded to the sink.  If this happens, attempting to force the sink loose may strip the CPU die of its upper cover or strip the entire CPU from the socket, both of which are undesirable events.  Go carefully, and don't force anything.

I think, but can't remember for sure, that Sony used thermal transfer pads on their CPUs in the Vaio machines I have looked at in the past.

Do you have a pet?  A dog or cat, perhaps, which may be shedding?  I have seen instances where pet hair/dander got sucked into a machine a clogged the heatsink fins on the fan so badly that I had to disassemble the laptops in question to physically clean the fins with a toothbrush and a pair of tweezers (gently, though, or you'll bend the fins!)

You might look on YouTube for a teardown video before trying to disassemble your laptop (unless you're already familiar with how it comes apart and goes back together).  A lot of the Sony Viao models are devilishly tricky to get apart.  (I just did a quick search, and didn't find your exact model, but there are several that might be similar enough to work from...)

A check at Sony's support page for this model did not turn up any teardown instruction (no surprises there...).

This vendor's page gives what might be good general instructions, and is for your specific model, but I DON'T KNOW (found them on a Google search):

http://www.cpu-fan-shop.com/sony-vaio-vgn-nr420d-cooling-fan.html

Good hunting on this one - keeping a laptop cool is almost always a challenge sooner or later.

Later On,
D

[frazelle09]

Oh, horusfalcan!

Thanks a lot for your detailed suggestion.  i haven't got time at the present to get into this laptop so i'll try some compressed air first.  It doesn't get used very much anymore - i'm taking something lighter - a Samsung Galaxy Plus 7.0 - on my trips.  It weighs a lot less and it's a lot easier on my back.  i think this is the same on our son and i had to tear down almost all the way to replace the rear AC connector port - or maybe not.  We found a set of pictures on the net and i d/l them, printed them out and then used them to place all the parts from each step on top of each picture - chuckle.

Thanks again for the very complete post as well as the URL.

Have a wonderful morning! 

[horusfalcon]

Hey, what can I say?  Hardware is my thing, the area in which I am strongest.  Glad to be of assistance, and hope things work out well for you.  Don't forget to angle your air stream in such a way that it helps remove dust instead of just packing it deeper.  (Why Sony and other vendors don't make the grille for the heatsink more easily removable is beyond me - that's usually the most troublesome area...)

Tell us how you like that tablet you're using - I'm lovin' my Nexus 7 (except for some early adopter's buyer's remorse - they just dropped the prices last week...  I've had mine for about two months now.  Great little tablet.)

Later On,
D