Pentium 4 not using SSE2 with Windows NT4
 

Hi folks,

I have been trying for a week to fix a problem with an overclocked Pentium 1.6A that apparently is not using the SSE2 optimizations. The OS is Windows NT4. I will post the abysmal benchmark below for your inspection...

Intel(R) Pentium(R) 4 CPU 1.60GHz
CPU speed: 2144.36 MHz
CPU features: RDTSC, CMOV, PREFETCH, MMX
L1 cache size: 8 KB
L2 cache size: 512 KB
L1 cache line size: 64 bytes
L2 cache line size: 128 bytes
TLBS: 64
Prime95 version 23.8, RdtscTiming=1
Best time for 384K FFT length: 56.260 ms.
Best time for 448K FFT length: 68.823 ms.
Best time for 512K FFT length: 75.053 ms.
Best time for 640K FFT length: 97.526 ms.
Best time for 768K FFT length: 121.935 ms.
Best time for 896K FFT length: 144.032 ms.
Best time for 1024K FFT length: 165.540 ms.
Best time for 1280K FFT length: 218.818 ms.
Best time for 1536K FFT length: 258.888 ms.
Best time for 1792K FFT length: 314.312 ms.
Best time for 2048K FFT length: 351.523 ms.

I have tried reloading the OS several times to no avail. This P4 is running from the i845 chipset, yes folks, that is SDRAM, all 1536 MB of it. I hated to part with that good RAM, but then buy a Windows OS that supported greater than 1 GB of RAM such as 2K or XP. Also we all know that P-1, stage two factoring, loves extra RAM, so I will use mine for a noble cause.

Does anybody have an idea of how can I implement the SSE2 opts so this P4 can actually LL test like a P4?

You could try to add CpuSupportsSSE2=1 to your local.ini file. See the undoc.txt file that came with the client.

PM

Does NT4 support SSE2 apps? I know Windows 98 did not. If you get a crash with the CpuSupportsSSE2=1 setting, then you know you'll need a more recent OS.

I will try first thing tomorrow morning and let you know what happens. I should have looked in the undoc.txt file before posting this inquiry but I only looked in readme.txt file. Thank you for all of your help!

Well I tried inserting CpuSupportsSSE2=1 into the local.ini file and sure enough, Prime95 crashes with a Dr. Watson for Windows NT box with the following message...

Application error has occurred and application log is being generated. Exception: illegal instruction 0x00001d.

The bottom line is that NT4 does not like SSE2. Looks like I will be searching M$.com for a NT4 patch for supporting SSE2. I will report back if I am successful. Again, thanks for all of your help!

[QUOTE=Prime95]Does NT4 support SSE2 apps? I know Windows 98 did not. If you get a crash with the CpuSupportsSSE2=1 setting, then you know you'll need a more recent OS.[/QUOTE]Windows 98 seems to work for me. The version is "Microsoft Windows 98, 4.10.1998" (Swedish language version). This benchmark is with default local.ini.

Intel(R) Pentium(R) 4 CPU 1.80GHz
CPU speed: 1906.65 MHz
CPU features: RDTSC, CMOV, PREFETCH, MMX, SSE, SSE2
L1 cache size: 8 KB
L2 cache size: 512 KB
L1 cache line size: 64 bytes
L2 cache line size: 128 bytes
TLBS: 64
Prime95 version 23.4, RdtscTiming=1
Best time for 384K FFT length: 19.788 ms.
Best time for 448K FFT length: 23.291 ms.
Best time for 512K FFT length: 26.591 ms.
Best time for 640K FFT length: 32.223 ms.
Best time for 768K FFT length: 39.287 ms.
Best time for 896K FFT length: 46.313 ms.
Best time for 1024K FFT length: 52.403 ms.
Best time for 1280K FFT length: 69.622 ms.
Best time for 1536K FFT length: 84.602 ms.
Best time for 1792K FFT length: 101.751 ms.
Best time for 2048K FFT length: 115.997 ms.

Maybe it was Windows 95 or a pre-service pack 98. It was a few years ago, so my memory is rusty.

Q: The SSE(2) benchmark crashes on my system!
A: If you're running Windows NT, install SP6. If you're running Windows 95 you'll need to upgrade to Windows 98/Me/2000/XP that support the new SSE(2) state.

From the [url]www.sisoftware.co.uk[/url] Sisoft Sandra page

PM

WOO HOO. Thanks Prime Monster! I just downloaded and burned NT4 Service Pack 6 from M$ to CD, installed it, now my P4 is cooking with gas!

Believe it or not, I bought this version of NT4 Server at an estate sale for five dolla' a few years ago.

Very Nice :smile:

PM

[QUOTE=Unregistered]I just downloaded and burned NT4 Service Pack 6 from M$ to CD, installed it, now my P4 is cooking with gas![/QUOTE]Make sure you install this too!

[url]http://www.microsoft.com/ntserver/sp6asrp.asp[/url]