I have built a fairly nice PC w/ an AMD 9550 Phenom cpu. But I'm not sure whether or not I'm actually using all four cores. I've installed the software that AMD has made downloadable for dual core processors and I think that it's working. How can I tell if I'm getting all the processing that I paid for? I have 4 gigs of 800 mHz ram (DDR2) and a Gigabyte MB that won't handle more than 800 mHz ram, SATA HDs, large PS, really big Thermal Take cpu cooler. Any suggestions? Oh, yes. I'm running Win XP SP-3.
All you have to do is open Windows Task manager to the performance tab, and see how many cores it shows and see if it shows activity on all of them. You wont be using all four cores all the time, but you should se some activity jumping around on each of them.
The amount of threads used depends on the program. Some programs won't utilize multi-threading. You can run Prime95 to see if all 4 cores do work. Also, Windows XP was released during the times when multi-core was unheard of. Windows 7 is optimized for multi-core cpus.
Seeing as your running DD2 Ram, I assume you are using a AM2/AM2+ mobo....Just keep in mind that some MOBO's will need driver/chipset updates.
I had to the same when i switched over from duelcore 4600+ to my phenom on my ECS mobo.