Areca ARC-1110 User Manual page 163

Q11: Is it possible to write software that will run on Intel's
processors with Intel® EM64T, and AMD's 64-bit capable
processors?
Answer:
Yes, in most cases. Even though the hardware microarchitecture
for each company's processor is different, the operating system
and software ported to one processor will likely run on the other
processor due to the close similarity of the instruction set architec-
tures. However, Intel processors support additional features, like
the SSE3 instructions and Hyper-Threading Technology, which are
not supported on non-Intel platforms. As such, we believe devel-
opers will achieve maximum performance and stability by design-
ing specifically for Intel architectures and by taking advantage of
Intel's breadth of software tools and enabling services.
Q12: How will Intel® EM64T work and what software is
there to take advantage of 64-bit extensions?
Answer:
Platforms with Intel® EM64T/AMD64 can be run in three basic
ways (note: a 64-bit capable BIOS is required for all three scenari-
os):
1. 32-bit O/S and 32-bit applications (Legacy Mode): No software
changes are required, however the user gets no benefit from
Intel® EM64T or AMD64.
2. 64-bit O/S and 32-bit applications (Compatibility Mode): This
usage requires all 64-bit device drivers. In this mode, the O/S
will see the 64-bit extensions, but the 32-bit application will
not. Existing 32-bit applications do not need to be recompiled,
and may or may not benefit from the 64-bit extensions. The
application will likely need to be recertified by the vendor to
run on the new 64-bit extended O/S.
3. 64-bit O/S and 64-bit applications (64-bit Mode): This usage
requires 64-bit device drivers. It also requires applications to
be modified for 64-bit operation and then recompiled and vali-
dated.
• For more FAQs, please visit knowledgebase of Areca
website at: http://faq.areca.com.tw/modules/smartfaq/
APPENDIX
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