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On 3/29/06, Lord Sauron <lordsauronthegreat@×××××.com> wrote: |
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> www.alienware.com I beg to differ. I could have sworn I saw a laptop |
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> with more than 2G... where was it... wow! You appear to be right! |
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> Darn.. I could have SWORN I saw something with > 2G... |
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|
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Actually, you are right. I neglected the monstrous Clevo laptop. Its |
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an AMD X2 with capacity for 2 optical drives plus 2 hard drives, up to |
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3G of memory, and a 200W power adapter. Weighs 12-15 lbs, _not_ |
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counting the power adapter! This is acutally a Clevo design, sold by |
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Sager, AGearnotebooks, and many others. Alienware got it with a |
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customized case. All of the reviews I read on it basically said |
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"incredible performance, excellent display, but heavy, noisy, and |
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really hard to describe how large it really is". |
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|
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I was actually considering purchasing this beast...but the noise |
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factor scared me off. Not really appropriate for a shared office or |
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conference room. |
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|
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> compiler helps with the 64-bit part. It gets a bit technical, but |
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> there is a big difference between something made from the ground up as |
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> 64-bit versus something that was made 32-bit and just recompiled |
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> 64-bit. |
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|
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For most applications, this is not true. The vast majority of C/C++ |
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code that runs on a desktop system couldn't care less whether longs |
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and pointers are 32-bits or 64-bits in size. It is a compiler |
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function to deal with that. And it is also a compiler function to |
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determine whether 64-bit or 32-bit registers should be used for a |
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particular operation. FYI, gcc has supported non-x86 64-bit CPUs for |
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a long time, so gcc's 64-bit support is probably more mature than you |
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think. So are the applications...many open source applications were |
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ported and adapted (if necessary) to 64-bit sparc and alpha processors |
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back in the late 90s. |
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|
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There are opportunities for some programs to take advantage of special |
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processor operations through assembly instructions. This is very |
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similar to how 3Dnow, MMX, SSE, et. al. make programs faster. So |
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there may be some specific optimizations for some operations that can |
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be improved over time. |
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|
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An example of an application domain that could benefit from 64-bit is |
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encryption, because for key setups you need to calculate very large |
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numbers. Such numbers could be calculated about twice as fast with |
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64-bit operations vs 32-bit. *BUT*, this does almost nothing for the |
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actual data encryption itself. |
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|
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A good resource on the 64-bit vs 32-bit issues is to look at AMDs |
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optimization guide for software developers. Chapter 3 is particularly |
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relevant: |
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|
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http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/25112.PDF |
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|
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-Richard |
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|
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-- |
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