RAM heat spreaders are there to look pretty, and have little if any functional value. Smooth metal does not dissapate heat into air. The difference in surface area is miniscule - we're talking 5, perhaps 10% tops (I'm sorry, claiming double or triple is flat out laughable). Compare your heat spreaders to CPU and GPU heatsinks. If you can find me one single air-cooling CPU/GPU heatsink that uses smooth metal surfaces, I've got a hundred bucks for you.
Im not saying they have a lot of function, but they do have some.
Now for surface area -- lets do some math:
Each RAM chip on a module: 70mm^2, at least on my Corsair modules. There are 16 per module. So thats:
70 x16 = 1120mm^2 of surface area. Now let's consider the surface area a heatspreader covers:
Each side of a module is ~2.5 x 10cm, which means that a heatspreader has 2500(4) - 1120(2) mm^2 of surface area that is not in contact with RAM chips. Thats roughly 77.6cm^2 of surface area over what the modules have alone.
Now, there may be variations based on the design of the heatspreader: OCZ ones for instance are grilles, and they do serve no purpose but to look pretty. On the other hand, those metal plates have a helluva lot more heat capacity than the chips alone, meaning there is more time for the heat to be pulled away from the chips before it becomes dangerous
I've worked with servers that handle many times more than you could ever dream of putting on your desktop - boxes that stay at 95%+ loads for months at a time. If there were any benefit to putting metal plates around our RAM, believe me we'd be using them.
Two things here:
1- I've worked with servers that have many timer more RAM capacity than desktops as well -- big honking Tyan ones with 16 slots, all loaded with 4GB sticks, so lets not use the "Im older, I have a job, I know more".
2- You're talking about DDR2 533,667 or at the fastest, 800 RAM. It is most likely running at 1.8v, and not producing nearly as much heat as DDR2 1066 CAS4 2.2v modules are. Im fairly certain that if I took off the heatspreaders from my RAM, id end up with some burned silicon, or at the very least, unstable RAM. (There is a good reason my Crucial modules, which are made using better chips, cannot match those speeds -- they dont have heatspreaders and become unstable at those speeds and voltages.)
Also, smooth metal dissapates heat quite fine. Ever look at a CPU heatsink? Notice how the individual fin blades are fairly polished? Heat spreaders look fairly similar. Usually made of the same stuff too -- aluminum. Aluminum also has a higher heat capacity than silicon per unit of weight. Silicon is ~19J/molK, Aluminum is 24J/molK. Even bearing in mind that those values can be affected by other factors, the heatspreaders still end up with the ability to dissapate more heat.
Feel free to correct me here though, but lets use some evidence.
