Conflicts between programs, look at the process list to see what the cargo you the process, I happened to have two antiviruses installed on that day, I created the conflict and put me at 100% cpu usage.

Hi:

Programs can not be because after formatting and installing the driver for the motherboard and install any program, it did.

Any additional software installed on the motherboard? Care, usually a shit, to myself the asus striker II NSE, a programmable I activated a process that gave me 25% cpu usage, I am looking for the post I wrote here at the time, anyway look at the process list to see if you find something there.

If none of this process to that percentage can be two things, a spyware, which is not discarded by the case and that has been formatted and that takes the prize you have the master disk in PIO mode, check the bios and the disk controller in device manager and make sure that this DMA disk activity.

Hello 4nt4r3x:
Since I've been respondents now move into the PC until you find what that tells me without much entropic.
I tell you, I have 2 SATA and PATA, the boot disk in which the operating system (XP) is a SATA and SATA installed in the primary.
In the device manager are enabled boxes' let BIOS select transfer mode "and" enable write caching "I imagine what he means is that the BIOS is the one that selects the transfer mode.
Looking in the BIOS in "Standard CMOS features" in the channel where the disk is connected, in "Extended ide driver" in this Order and "Access is also in AUTO mode.
Do I have to change anything?

Watch to activate the DMA in the BIOS, what chipset your board mounts?

Yes, the enforce problemillas gave occasionally to set the record as DMA, try reinstalling the enforce drivers on your system to see if you resolve, so that even if you follow the same test to enable DMA in BIOS .

Hello 4nt4r3x:
Firstly thank you very much for your time.
I tell you, in BIOS under "Integrated periphericals" in the "ide dma transfer" as in "sata dma transfer" option in this "enable", which I imagine is what you said about activating it in the BIOS.
I just made another test, I disconnected the SATA and PATA changed the old one I have (and I've formatted) if the problem was the SATA channels, but nothing remains the same.

in the process on the system dialed down 90%-odd I suppose, the task manager is not very good, download the "Process Explorer" and see the CPU usage of "interrupts" and "DPCs" if they consume much you have problem with some components and / or their drivers, would be a matter of locating it is.