However, what is really strange is that when I play SC, my mac heats up like an oven. My Mac is far cooler, however, when playing WC3. Why is this?
I am guessing that there is no frame limit or vertical synchronization. Basically the process will use 1 core at 100% all the time as it has an infinite work load.
WC3 is graphically accelerated using Direct3D 8. This means that most of the complicated graphic calculations are done on the GPU which does them several fold more efficiently than the CPU. On the other hand SC1 was probably before graphic standardization took off (most computers had no graphic accelerator, those that did had one of many different competitors) so will be using the CPU to generate the graphics. Without a frame limiter or some form of vertical synchronization the game will render an infinite number of frames per second limited only by resource availability, using all free resources. The combination of extra CPU work and no GPU work will mean the processor has to run at full clock speed and do more work.
There is also a chance that SC1 is less optimized for modern hardware than WC3. Specifically if SC1 used a lot of CISC assembler this could be the case. All the old 16 and early 32 bit instructions were marked as deprecated after major design revisions required for high speed operation and as such modern processors are no longer optimized to execute them. In fact, many very old instructions are run using internal micro-code instead of fixed hardware units. Calling these functions excessively (like an old program with infinite resource demand) could cause the processor to run hotter than usual since it is using features not well optimized or not even used by recent programs. This would especially be the case with the software graphics as those were often highly optimized for hardware at the time using features that were deprecated for inefficiency. Yes the game works fine but that is what >3GHz more clock speed (entire orders of magnitude) does, it does not mean it is working as fast as it should with the available resources however.
Neither computer should get hot from those games. Maybe if you play a map in WC3 which has a lot of units on screen, they might get hot, but else they shouldn't.
Laptops will always get hot as they prefer passive cooling as active cooling uses power. Also the fact he is not natively running Windows (running it virtualized in MAC OS) and MAC OS graphics itself is not the best (all Linux based graphic systems are not that efficient due to some design flaws from old main-frame days) will mean more resources are used than should be. The difference in temperature is due to the difference in hardware being used to run the process.
The best example I can give is with the recent SC2 game running on a GeForce 8800 GT. That card can run WC3 with max AA and everything perfectly and remain cool. It can also run TES Oblivion maxed out, even with AA and still remain cool. However as soon as you run SC2 at any setting that pushes the card (shaders above low) it quite literally overheats and people even had it catch fire. The reason can only come down to SC2 using Direct3D 10 (only of those 3 games mentioned) which when the 8800 GT was designed was still new (GeForce 8 was first to support it!) so hardware was not yet fully optimized for it. Running these D3D 10 calls caused more power to be used resulting in heat beyond the designed capabilities of the card so it would burn out.
Similar could be happening with SC1 on his mac where the processor, being modern, is designed around running newer/specific instructions fast and efficiently while old instructions are only there for compatibility. I am not sure the people at Intel even consider operating power when running legacy programs as a problem as they should use so few clock cycles that even if it works inefficiently the processor will still operate within its specified power consumption. However a badly written legacy program, running inefficiently in a virtualized operating system without any limit on resource consumption could cause a problem.
My suggestion is to install a parallel OS, Windows 7/8. Instead of virtualizing Windows in MAC, restart the computer and boot into Windows directly. This avoids unnecessary overhead and also allows for more efficient operation.
It could be something dumb like because SC1 uses software render, it generates a lot more interrupts which are expensive to handle (need a lot of resources) due to virtualization.
