mprime misdetects processor on microsoft xbox

[mda2376]

After a little experimenting mprime does not properly rechignize the processor in the microsoft xbox. It is a slightly non-standard version of the mobile celeron at 733 mhz. The operating system is gentoox, running kernel 2.4.20. While setting up mprime, it shows:

CPU Information:
Unknown Intel CPU
CPU speed: 733.42 MHz
CPU features: RDTSC, CMOV, PREFETCH, MMX, SSE
L1 cache size: 16 KB
L2 cache size: 128 KB

Which seems somehat correct, but after checking my listing on primenet, I now have one machine listed under "Intel 486" with a completion time of over 400 days!

The linux kernel has this to say about the processor:

meatbox mprime # cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 8
model name : Celeron (Coppermine)
stepping : 10
cpu MHz : 733.326
cache size : 128 KB
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 2
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 mmx fxsr sse
bogomips : 1461.45

It would be interesting if this could work, I would love to put my xbox to work when it dosent have anything better to do. I havent had a chance to look at the cpu detection code, I cant imagine this being a difficult fix.

Matt

Ah, you are using my idea! :idea:

This is the way of the future. :D

[mda2376]

Have you tried running mprime on the xbox's celeron processor? and did it give a similar result?

No, I have not.
But I actually came up generally with the idea a couple years ago.
Check out my threads.

The complete idea is to, have a small portion of the computing power, to go to an actual prime95 game.

I have done this by using turbocad floor designer.
There are square rooms, arranged in the prime number spiral.
The object is to find the mersenne prime rooms.

I then have expanded this, to several subsets of primes, using properties of the math, to navigate through.


I have written up about 50 ideas, with tweaks and twists, like multi level buildings of the prime numbers spiral.

If you ever get your end working, all we need is someone who could combine my files with mprime.

:D :D

[clowns789]

Just what I was thinking too! Must be ESP :D

Maybe you could tell me how do it if and when you do it or like TTN said I could keep a game running for a long time. Maybe I could download and burn a CD.

[mda2376]

I've written a simple patch to properly identify the celeron 2 chip in the xbox (and also applies to any other celeron 2, the celeron 2 mobile, etc) with a p3 core. It seems that whenever mprime dosent rechignize a chip, it considers it to be a 486..

patch is againt cpuid.c in source/ from version 23. I've also built a shared and static'ly linked binaries if anyone is interested. Maybe someone will pass along my patch to the maintainer for a future version?

all files available here:
http://evopvr.sourceforge.net/mprime/

Hmm.. now if someone could only update primenet with the most recent CPU_TYPE codes so my p4 xeon's show'd up as something other than "Unspecified type"...

Enjoy

Matt

[S00113]

Originally Posted by mda2376

I've written a simple patch to properly identify the celeron 2 chip in the xbox (and also applies to any other celeron 2, the celeron 2 mobile, etc) with a p3 core. It seems that whenever mprime dosent rechignize a chip, it considers it to be a 486..

Your patch is still not included. 23.5.2 also fail to detect the Celeron 2 in the XBox.

I worked around it by setting

[pre]CpuOverride=1
CPUType=8
CPUSpeed=733[/pre]

And in case anyone are interested, here is the benchmark:

[pre]
Unknown Intel CPU
CPU speed: 733.00 MHz
CPU features: RDTSC, CMOV, PREFETCH, MMX, SSE
L1 cache size: 16 KB
L2 cache size: 128 KB
L1 cache line size: 32 bytes
L2 cache line size: 32 bytes
TLBS: 64
Prime95 version 23.5, RdtscTiming=1
Best time for 384K FFT length: 91.821 ms.
Best time for 448K FFT length: 110.376 ms.
Best time for 512K FFT length: 121.855 ms.
Best time for 640K FFT length: 166.241 ms.
Best time for 768K FFT length: 198.702 ms.
Best time for 896K FFT length: 242.205 ms.
Best time for 1024K FFT length: 271.434 ms.
Best time for 1280K FFT length: 362.497 ms.
Best time for 1536K FFT length: 441.886 ms.
Best time for 1792K FFT length: 537.289 ms.
Best time for 2048K FFT length: 599.081 ms.
[/pre]

Not bad for a Celeron!

[Prime95]

I just noticed this thread and will add the patch to the source. I don't understand why you would want this reported as a Pentium III (cpu type 10) rather than a Celeron (cpu type 8)

[S00113]

Originally Posted by Prime95

I just noticed this thread and will add the patch to the source. I don't understand why you would want this reported as a Pentium III (cpu type 10) rather than a Celeron (cpu type 8)

Without any patches mprime will detect it as CpuType=4. 8 would probably be the best choice. /proc/cpuinfo says:

[pre]
vendor_id : GenuineIntel
cpu family : 6
model : 8
model name : Celeron (Coppermine)
stepping : 10
cpu MHz : 733.324
cache size : 128 KB
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 2
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 mmx fxsr sse
bogomips : 1461.45
[/pre]

[Tasuke]

The processor on the xbox is not a celeron, but an actual P3, with the cache cut down. There is no loss of bus width like on a celeron(where the cache blocks were disabled which causes half the bandwidth)

[lozcs]

Hi folks, I'm new to this board but been running Prime95 for over 8 years... (nearly 1000 CPU years now!)

I have recently been introduced to Xbox Media Centre (www.xboxmediacenter.com) It's a fantastic way of playing all my media from my PC.

Since my Xbox is now on 24/7 and connected to the net anyway I wondered if anyone out there knows how I can run LL's with my xbox - at the same time as XBMC would be fantastic.

Regards,

Lawrence......