Performance issue

First of all sorry , I´m a bit ashamed to open a treat for this ,but I´m stuck here since a week and I’ll be damned if I know what the problem is!

Playing araond with the new Blender Versions I noticed an immense perfomance drop after 2 minutes of modelling , increasing until after 10 minutes Blender was totally stuck with 100% Cpu load.

My first explain was the meshundo consumes to much power with my crappy 800Mhz, and building up a new system at this moment I diddn´t cared much about it.

But with the new System up and working, the same problem appeared,and not only this.The Problem also appears on older Blenders (2.25) so it cant be new features at all. Still after a few minutes Blender consumes more and more Cpu load, until a mousemovement (only in Blender win) gives a full 100% (which are now 3200+) :x

I tried different Graphic drivers Catalyst 3.5 - 3.10 and with no changes!In fakt I tweaked anything that came into my mind without an effekt an this problem.
From the fact that it works fine if I close Blender and reload emmediatley ,It´s an Windows prob but I´m realy short on ideas right now, and to ask here is one of those last ones .

Anybody an idea ore simular experiences?

WinXPPro Sp1 / Radeon9500(TwoHeaded) / XP2500+ / InfineonDDR400

you know the catalyst drivers are up to 3.9?

(I bet it isn’t blender, what else are you running? also, it could be your sound card, try running blender with audio truned off in the info button prefrences or with the -noaudio switch)

I´m using 3.10 right now

Seems APIC was the Name of the Bastard.I switched from APIC to ACPI in the Hardwaremanager and EVERYthing got an dramendous speed boost.

A REAL good tip for everyone with an nforce board byEpox [!]

Thanks anyway