What's New: New Features in Version 24.x of Prime95

 

NEW FEATURES IN VERSION 24.x of PRIME95.EXE

New Features in Version 24.14 of Prime95

1.  A bug that caused the torture test to hang on 256K FFTs on SSE2 machines with 128K of L2 cache was fixed. 

New Features in Version 24.13 of Prime95

2.  Celeron D (256K L2 cache) and Willamette (also 256K L2 cache) now have different implementations for several FFT sizes. This results in an improvement of several percent for the Celeron D. 

3.  A bug that caused some machines to generate "Error 2252" when communicating with the server was fixed. 

4.  SSE2 trial factoring code had a bug when factoring very large exponents.

New Features in Version 24.12 of Prime95

1.  For SSE2 machines the larger FFTs have been changed to more effectively use a wide variety of L2 cache sizes. The previous version was optimized for a 256KB L2 cache only. Depending on your CPU and FFT size, you could see an improvement of several percent. 

2.  As a side "benefit" even larger FFT sizes are now supported. This allows testing of exponents up to 596 million. Not recommended. 

3.  The factoring breakeven points have been recalculated using my 2 GHz P4. This version of prime95 will do less trial factoring.

4.  Since server database crashes cause spurious error 3 messages, prime95 will now ignore error 3 messages from the server for 72 hours. This should workaround the problem whereby a result is reported but no CPU credit is given and the reservation is not cleared. 

5.  Fixed crash bug trial factoring exponents above 286 million.

New Features in Version 24.11 of Prime95

1.  Faster FFTs for AMD64 using prefetchw in both 32-bit and 64-bit mode. You can expect about a 15% speed improvement.

2.  Prime95 now detects support for 3DNow! instructions. See undoc.txt for overriding this detection with CpuSupports3DNow=n in local.ini.

3.  Factoring entries in worktodo.ini now accept exponents up to 2 billion.

4.  Improved checking for memory allocation errors during a torture test. Better guessing of amount of memory to use in a blend test.

5.  Added timeouts to PrimeNet communications in hopes of avoiding rare hangs when contacting the PrimeNet server.

6.  Fixed rare bug where P-1's GCD could miss a factor.

7.  Added trial factoring to the benchmark.

8.  Fixed bug in ECM when using zero-padded FFTs.

9.  SSE2 macros optimized for an additional 1-3% improvement on P4 and AMD64 CPUs.

New features in Version 24.10 of Prime95

1.  64-bit version of prime95 available for 64-bit Windows.

New features in Version 24.9 of Prime95

1.  Fixed crash when running on machines with "no-execute" protection.

2.  Fixed mis-detection of some P3 and Celeron CPUs.   

New features in Version 24.6 of Prime95

1.  Athlon users should see a 20% to 30% speed increase. 

2.  Pentium, Pentium II, Pentium III users should see dramatically WORSE performance. Run version 23 instead. 

3.  P-1 and ECM now support numbers of the form k*b^n+c. This cannot be done from the menus. Add these entries to worktodo.ini:

Pminus1=k,b,n,c,B1,B2
ECM2=k,b,n,c,B1,B2,curves_to_do[,specific_sigma]