On 20 Nov 2001, at 21:11, George Woltman wrote: 

> At 07:54 PM 11/20/2001 -0500, A & T Schrum wrote:
> >I looked but hadn't found how an AMD XP 1600+ should identify
> >itself within Prime95. It calls the processor a Cyrix 6x86 running
> >at 144 MHz when it is running on a 1400 MHz motherboard. I set it
> >to an Athlon at 1400, are the settings correct for an AMD XP 1600+?
> 
> Yes.  BTW, if someone wants to improve the code in prime95 to
> properly identify AMD chips, I'd be glad to include it in a new
> release. Contact me and I'll point you at the code that needs
> tweaking.

I changed the CPU in one of my systems (running mprime) from 
Athlon 1200/266 to Athlon XP 1700+. I did nothing except change 
the CPU speed in the menu. The speed improved - by about 17%, 
which is about what is expected - and it's running 7C cooler, but 
that almost certainly has more to do with the fact that I also 
changed the cheap "AMD approved to 1.3GHz" CoolerMaster 
heatsink/fan for a Thermaltake unit (with the 26 cu ft/min YS fan, 
not the 38 cu ft/min Delta fan, which might do a better job of 
cooling but is _very_ noisy!)

Is there an issue here in that Prime95 (& presumably NTPrime) 
detects the processor at startup but mprime doesn't? Or does the
program only "guess" the CPU type & speed when the program is
installed?

BTW Athlon XP all run at 266 FSB. It looks as though the "speed 
rating" relates to the actual core speed as follows:

Take "speed rating" (1600 in the case of an Athlon XP 1600+)
Add 500          (2100)
Divide by 1.5    (1400)


Regards
Brian Beesley
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