How much thermal paste to put on P4 3.2 GHz CPU

[Sarmad]

I need to re-apply a fresh new layer of thermal paste between my CPU and heat sink (I'll be cleaning off the old layer with isoproply alcohol). It's been several years before I last did it. How much paste do I need to put on? The CPU is an old Intel P4 3.2 GHz Northwood (old but it still does what I need this particular PC for). Articles I read about applying thermal paste are very vague, they just say not too little (or it won't be enough to do the work) and ot too much (or it'll insulate rather than aid in cooling). Some diagrams on the Net show "this is too much" but there's never a picture showing the right amount. The paste I'm using is Akasa 445, but I don't think the type of paste matters regarding the amount needed. If I was to put a blob of the paste on the CPU before spreading it, how big should this blob be so I know I've put on enough? Some reports say the size of a grain of rice whereas others recommend the size of a pea, which is a big difference.

Thanks in advance.

 

[captaincranky]

I'd go with, "the size of a grain of rice". If applied at the correct thickness, "the size of a pea", would just about cover the entire motherboard!

All that's necessary is a very thin film. I personally use a brand new single edge razor blade the spread the material. If you're feeling clumsy, paranoid, or are actually clumsy, you can use a credit card also. But, IMO a credit card makes more of a mess, since more of the material is prone to stick to it.

 

[Sarmad]

Thanks CaptainCranky,

Just to be sure, I only need to apply the paste onto the CPU, not on the heatsink too?

 

[Leeky]

Just the CPU, otherwise you'll have too much and compromise the thermal properties of the paste.

I generally use the "grain of rice" method, and as of yet have had no issues.