There are two main causes that could lead to Prime95 slowing up a machine. - The first cause is memory size, this could only happen during the second stage of P-1 factoring, that is 2% of the time it takes to fully test an exponent. This could only happen if one had allocated to much memory to this process via the option "Options / CPU / Daytime available memory and Night-time available memory". Most of the time Prime95 uses less than 25 MB (if busy on the current exponents.) So if swapping occurs it is due to the combination of quantity of memory, OS and other applications. (Try running a few MSOffice applications together on an XP machine with less than 512MB of memory.) Insufficient memory can be detecting by the fact that just bringing an application to the foreground induces a lot of disk activity. Or more precisely by using task manager and looking at the amount of used memory (Commit Charge) versus the amount of physical memory. If the first is smaller than the second you will have memory swapping to disk.
- The second cause that could bring a machine to become very slow because of Prime95 running, is thermal throttling. This means that the processor detecting its temperature is to high starts to slow down. This is due to insufficient cooling. The diagnostic can be done via freeware utilities like ThrottleWach (http://www.panopsys.com/Downloads.html for instance) The causes can be multiple: - dust accumulation on coolers, venting openings in the case and fans. The solution is obvious: clean up. - overclocking the system. Again the solution is obvious, overclock less or not at all. But I suppose that some prefer a machine that can run at 4,5 GHz for a few seconds to a machine that runs at 3 GHz all the time. - poor design of the machine. Here the solution is less obvious, change the CPU cooler, add fans... If you are not familiar with machine building, you should get the help of a professional. If the problem occurs on a portable there is little you can do except throttling prime95, see the undoc part of the help or readme file. The only thing is to diagnose which of the problems one is having. To sum up Prime95 is not likely to induce memory swapping, this could only happen for a short time and if prime95 is specially configured to use a lot of memory. Prime95 making use of all the idle time of your CPU could cause it to heat up. Put this means you have a hardware problem. Any program needing 100% of CPU for some time would have the same effect. Jacob Visser _______________________________________________ Prime mailing list [email protected] http://hogranch.com/mailman/listinfo/prime
