I think my P4 is running like a P III, at one third speed doing Mersenne
Prime testing.
When I run Prime95v22 it reports my P4 as .... CPU features: RDTSC, CMOV,
PREFETCH, MMX
If I change the CPUtype to 12 (P4) and add SSE to the local.ini file, as in
... CPU features: RDTSC, CMOV, PREFETCH, MMX, SSE nothing changes.
If I change SSE to SSE2 the system crashes with an illegal instruction
message.
I am running Prime 95 on a 256 meg. P4-1600 with 8k L1 and 256K L2 on
Windows 95A
I'm entertaining these theories:
Windows 95a without drivers? doesn't support a P4. (Is it being asked to?)
I don't really have a P4. (I bought this system expecting P4 performance
running Prime95)
L1 cache too small.
L2 cache too small
Something else.
Comments/theories/assertions/wild hairs are invited.
My best times my P4 1600 256 meg 133SDRAM
Best time for 256K FFT length: 57.218 ms.
Best time for 320K FFT length: 71.299 ms.
Best time for 384K FFT length: 86.423 ms.
Best time for 448K FFT length: 102.487 ms.
Best time for 512K FFT length: 115.680 ms.
Best time for 640K FFT length: 148.042 ms.
Best time for 768K FFT length: 184.596 ms.
Best time for 892K FFT length: 214.233 ms.
Best time for 1024K FFT length: 250.226 ms.
Best time for 1280K FFT length: 320.198 ms.
Best time for 1536K FFT length: 386.440 ms.
Best time for 1792K FFT length: 467.666 ms.
>From the Benchmark site
P4 1500 133SDRAM 256 Full
0.019 0.024 0.030 0.035 0.040 0.052 0.063 0.079 0.087 0.120 0.154 0.196
19 24 30 35 40 52 63 79 87 120 154 196 Mersenne benchmark times from
http://www.mersenne.org\bench.htm
P III 1 gig times are below
Intel(R) Pentium(R) III processor
CPU speed: 996.59 MHz
CPU features: RDTSC, CMOV, PREFETCH, MMX, SSE
L1 cache size: 16 KB
L2 cache size: 256 KB
L1 cache line size: 32 bytes
L2 cache line size: 32 bytes
TLBS: 64
Prime95 version 22.3, RdtscTiming=1
Best time for 256K FFT length: 54.165 ms.
Best time for 320K FFT length: 70.726 ms.
Best time for 384K FFT length: 84.818 ms.
Best time for 448K FFT length: 101.149 ms.
Best time for 512K FFT length: 114.412 ms.
Best time for 640K FFT length: 148.319 ms.
Best time for 768K FFT length: 180.532 ms.
Best time for 896K FFT length: 212.317 ms.
Best time for 1024K FFT length: 243.061 ms.
Best time for 1280K FFT length: 315.420 ms.
Best time for 1536K FFT length: 377.044 ms.
Best time for 1792K FFT length: 448.984 ms.
>
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