We have a computation intensive 16-bit application that we've noticed takes a significant performance hit moving from an 800 Mhz Win2K Pentium-3 Dell to a 1.8Ghz WinXP Pentium-4 Dell (both notebooks). We tested on an HP WinXP notebook with the AMD Athlon at 1.6Ghz and found better than double the performance for the AMD vs the Pentium-4.
Can anyone comment on why the Pentium-4 is so much slower? Is it not as well optimized for numerical computations as the Pentium 3 or the AMD Athlon? Or could the Pentium-4 speed-step simply be brain dead?
Sounds like it was a propriety product you were using. Much of these programs are specifically written for a certain platform and architecture. The Athlon's is a lot closer to the P3's (which it was probably originally written for) than the P4 is. If you have the code in C/Fortran/C++, I suggest downloading (actually buying if you're using it for commercial use) Intel's compiler and using the -qax (I think that's it) tag to have it auto-vectorize and optimize for the P4 platform. You can get a huge increase in performance with the right optimizations. Aces did a review of vector optimization a while ago and with a specific FP program (that was already well optimized for the P4), using the -qax flag for auto-vectorization brought about a 300% increase in performance.
"We are Microsoft, resistance is futile." - Bill Gates, 2015.
The P4 doesnt do well with the type of aplications you are talking about. (IE. Basic number crunching apps.) The FPU on the P4 sucks realy bad. You made a mistake geting a P4 for what you are doing. The P4`s only strength is in 3D applications and multimedia. Sorry but you are screwed unless you can replace that laptop.
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