How PIII new SSE are used?

[Zanna]

Hi Murcers!

I've finally gone onto a PIII system, changing my old PII 400 Mhz (only the CPU) with a PIII 500 Mhz (not overclockable! )

Does anyone knows how are used SSE instructions into Windows 95 OSR2.5 (i think NOT used....) and DirectX 7 (maybe they are used ?) and if there are some patches to make it working?

Thanks in advance ....

Zanna

[CHHAS]

The "non-overclockable" part sounds a bit strange, how have you tried to OC it ?

Windows 95 does not use SSE instructions, DirectX 7 however does, how well, I'm not quite sure.



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P3 500@560, 192 MB ram, G400 16SH

[Zanna]

CHAAS, I stated that my PIII was not O-C because I tryed to O-C him trought SoftFSB.

When I only tryed to O-C to 104 FSB my system crashed. Maybe Intel have taked some precautions in order to make the CPUs unoverclockable ?

Previously I overclocked my PII 400 Mhz to 112 FSB without problems (448 Mhz). (and my Matrox G400 Max does not have any problem to follow this "terrible" AGP bus speed).

There be any way to see if SSE instruction are enabled under DirectX 7 + Win 95, e.g. to test or verify speed improvements using this instructions?

[This message has been edited by Zanna (edited 26 January 2000).]

[CHHAS]

Tough luck with your P3, mine'll do 560, but not 620, because of the level 2 cache

I don't think there is any way to turn off SSE acceleration in DX7, so as long as it's installed you should be OK.



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P3 500@560, 192 MB ram, G400 16SH

[Nuno]

DirectX 7 only uses SIMD (SSE, 3Dnow!) intructions to its full potential when Dx7 T&L code is used. All the present games are using their own software T&L engine (with more or less SIMD optimizations) just because DirectX T&L code sucked. But I think Dx7 will be used more and more because:
1 - It is definetly better than its predecessors.
2 - With all this buzz about T&L capable cards, in order to use that capability, the T&L must be done trought Dx7.

I´m most impressed with Dx7 T&L and SIMD optimizations. Running DMZG (that hi-poly count bench from Nvidia to show off T&L) in a celery 450 gave me 19 fps. An athlon 500 does 35 fps. I realize that the athlon has a heck of a fpu, but a 84% speed increase with a 11% cpu clock speed increase reveals some 3Dnow! magic...

[Zanna]

OK, Nuno.

I think you should be correct, but I guess if you used Windows98 or Windows95 (SSE not enabled in W95: is true or not?).

I think this type of instructions does require an operating system support to work properly. I remember that Intel has implemented SSE trough changing the processor "mode" (adding another model over those used by windows). This mode must be supported by the operating system, of course.

AMD maked thing muchs easyer, adding only the instructions and not requiring to enable another special processor mode to use it.

My opinion is that Intel approach is technical better but into the real word the best thing is done by AMD, because is more "compatible" with older software.

I don't know if Microsoft enabled SSE into DirectX 7 forcing eventually W95 to run in that mode, but i Think 3DNow! Instructions should work anyway. I know Intel made some drivers for NT to enable SSE (in order to have applications like 3D MAX running on PIII at max speed) and those drivers must be used in conjuction with specific NT Service Packs.

One thing sure it's that I want to see what Matrox have done with OGL in next G400 driver release... using T&L crunched out by a PIII...

Cheers....

Zanna.

[fds]

If Control Panel - System - General says you have a Pentium III, you should be fine.

If not, you should get Win98.

[Nuno]

Hi there

Don´t really know if win95 supports SSE or not. To be honest I wasn´t aware of the need to change the cpu mode in order to SSE to work. AMD doesn´t need it? Good! AMD 1 Intel 0

DX6 suported 3DNow!. I think Dx7 suports both 3dnow! and SSE.

There is a way to find out if your CPU SSE is used or not. Get 3dmark99 max. If SSE is used, you shoud get 5000+ 3dmarks. If not you may get around 3800. 3dmark uses SIMD instructions (an it makes a huge diference) so run it.

using T&L crunched out by a PIII...

Crunched by an Athlon/3dnow! would be far more impressive

[Zanna]

OK...
fds, you like Win98 -- I don't.
Nuno, you like AMD -- I not!

I respect yours opinions... honestly AMD make a great job with Athlon and WIN98 SE is more better than WIN98 (so buggy!) the only thing that I was curios to know is the thing that I declared into the name of this topic...

I taked some informations.

PIII need to be putted in a particular "status" to handle properly SSE, and the O.S. must catch some particular type of exceptions insthead of believe that an error has occurred.

These informations can be found on http://developer.intel.com
If anyone want the exact URL where those thing are explained, I can re-find then post the correct URL.

I definitely think: only if Microsoft maked some tricks into DirectX 7 those instructions are enabled on Win95.

A simple program to check if SSE is enabled onto a particular system is on the Intel site, but I haven't the Visual C (I think version 6) compiler needed to make it.

Anyone Can?

Cheers, Zanna

[Zanna]

Only for reference:
http://developer.intel.com/vtune/cbt...tes.htm#AP-900
http://developer.intel.com/vtune/cbt...imd/900lic.htm

Bye Bye ..... Zanna

[fds]

Zana, I hate Win98, SE or not. I'm a long-time NT user (since 3.1 beta ). Unfortunately until companies finally start releasing full-featured Windows 2000 drivers, I'm stuck with dual-booting to Win98SE now and then.

[fds]

By the way, try this one: http://support.intel.com/support/pro...s/frequencyid/

[Nuno]

Zanna: Please use my 3dmark99 tip to check the performance, with win95 and dx7.0. If you get a value around 5000, trust me, I don´t know how or when, but that SSE has to be in use.

Oh, and I´m not an AMD fan. I´ll buy the best cpu for the money, I don´t care if it´s Intel, AMD, Cyrix, or McDonalds . And in the present time, Athlons offer the best price/performance. In the future, if AMD makes CPU *deliberatly* incompatible with present slotA mobo´s (I bet that if AMD was Intel all slotA users would have to upgrade to a mobo with a purple slot for the .18u Athlons to work), and if Intel releases a killer cpu (maybe another celeron 300-366 like) you bet I will buy Intel again.

[This message has been edited by Nuno (edited 31 January 2000).]