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CPU hunger...how much?

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Old   October 12, 2005, 15:18
Default CPU hunger...how much?
  #1
rachid
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Hi,

During meshing with GAMBIT and iterations with FLUENT, my computer slows down too much and a few tries takes many hours.

Even sometimes my PC becomes "not responding" when i work on meshing 3D.

My question is I plan to buy a new computer with 2 CPU s and 2048 MB ram just for this reason (the best configuration from the shop). So do I experience visible speed up or at least do I have more efficient work on 3D models?

Y configuration is now AMD athlon 1.8+Ghz and 512MB ram.
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Old   October 12, 2005, 16:38
Default Re: CPU hunger...how much?
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Ahmed
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If you want to see real improvement you have to go for better microprocessor (Forget about the pentiuum family in plain english)
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Old   October 12, 2005, 17:32
Default Re: CPU hunger...how much? *NM*
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rachid
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Old   October 12, 2005, 17:32
Default Re: CPU hunger...how much?
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rachid
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Which processor do you advice? 2 processors or single?
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Old   October 12, 2005, 20:06
Default Re: CPU hunger...how much?
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Ahmed
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If you are stuck with intel, you can look for their Itaniuum Processors (two is better than one) otherwise you have silicon graphics or sun. Remember Mac processors are faster than all pentiuum. there are other factors that affect the speed of execution e.g. the swap area is really important, the amount of RAM installed and the operating system (Linux is much more stable than windows) the file system (all windows impose a limit on the maxiumum file size unless you use the NFS not the FAT32) Of course your final decision is going to be limited by the amount of dollars available. Hope that will help

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Old   October 13, 2005, 06:16
Default Re: CPU hunger...how much?
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Charles
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Rachid, 2 CPU's only make sense if you have a license which will allow you to use more than one at a time. But even upgrading to the latest spec single CPU system will give you more or less double the performance of your 1.8 Athlon, and 512 MB is nowhere near enough to do much CFD. You need at least 2 GB, and for a 2 CPU system at least 4 GB. I wouldn't bother with the expensive "heavy metal" machines, such as Itanium or Sun. Top-end AMD Athlon 64 or Pentium 4 is good choice for a single CPU system, Opteron 252 or Xeon 3.6 for a dual. I've done some tests (e-mail me and I will send you the results) and in Fluent there is not that much difference between AMD and Intel. I'm not sure how cost-effective the new dual-core A64 X2 and P4D systems are, has anybody tested them? The 3.2 GHz P4D has produced some impressive SPECfpRate results, considering its low price, and I would be curious to know if that translates to real world performace.
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Old   October 13, 2005, 14:46
Default Re: CPU hunger...how much?
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rachid
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Thank you for your help.
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Old   October 13, 2005, 23:03
Default Re: CPU hunger...how much?
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Ahmed
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Charles Itaniuum is the latest processor produced by intel (it is not a "heavy metal" machine as you call it) to compete against Silicon Graphics, Sun and other dedicated processors Ask them why? I have read on this forum that the AMD Opteron processor is behaving well on CFD applications, that might be another option available to Rachid.

Rachid, if you are running your application on a windows XP or NT then you can check the performance of the computer, right click on the bottom part of your window, select Task Manager then select the performance tab. This will display how much of the Ram being used and how much of the cpu is used. That should give you a good idea on what to do Hope this will help.
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Old   October 13, 2005, 23:17
Default Re: CPU hunger...how much?
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Charles
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Fluent have performance measurements for various systems on their website. When I last looked the figures for Itanium 2 were not that impressive, when you consider the difference in price, which is rather large. Actually, the CPU to have is probably IBM's Power 5, but that is expensive heavy metal.
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