They do more POST checking. A good memory test alone can take 5 to 10 seconds to run.
I also don't think that they intentionally obfuscate them, from the two BIOS engineers that I know and have talked with, they go to great pains to try and keep everything clean and be very deliberate and complete in their coding, very defensive. When it doesn't work, it doesn't work, you can't just but a debugger on it, you can't even put an ICE on it with a modern chip. From what I gather, when they run across a bug their typical strategy is to sit and think about it until they come up with an idea as to why it may be broke. Phoenix and AMI may have some kind of reverse engineering prevention but I don't think that it would be that much. It shouldn't be enough to make the kind of performance difference we're seeing. "Eric W. Biederman" wrote: > LinuxBIOS with the CPU cache disabled 5-7 to when the OS was loaded on > a server board. I did that by mistake once. Totally smoked what the > OEM BIOS was doing. > > Plus I find it very attractive to make the argument that OEM BIOS's > are slow simply because they are proprietary. > > If someone can find a better explanation, I'd love to hear it. > > Eric > > "Preston L. Bannister" <[EMAIL PROTECTED]> writes: > > > How about simply because the LinuxBIOS code: > > > > 1. Runs 32-bit instead of 16-bit code. > > (I remember a 2x improvement rule-of-thumb). > > > > 2. Runs at full clock rate. > > (Quite a difference between 6 and 600 Mhz - if different). > > > > 3. Enables the CPU cache. > > (Could be another 10x or better factor there). > > > > Not that I know exactly what your typical OEM BIOS does... :) > > > > I'll bet the about pretty much covers the difference. > > > > From: Eric W. Biederman > > > I have wondered for the longest while why linuxBIOS can so easily be > > > faster than the legacy BIOS's. And I have come up with an interesting > > > hypothesis. Other BIOSs are obfuscated to prevent reverse > > > engineering, and to hide their secrets. My only guess is this tangled > > > up code slows them down.
