High CPU Temps and Choppy Streaming Video

For about the last 2 weeks I've been having issues with choppy video playback while streaming. The audio has generally been good, just choppy video.

At first I though maybe I was having internet connection issues, so I took my router out of the picture and connected my laptop directly to the cable modem. After running a bunch of speed tests, I felt that my connection wasn't the issue. I called Netflix, and I have to say I'm amazed at the information they can track from your computer while you're streaming movies. The tech that I spoke with said that while streaming he could see that my processor was maxing out, and that was more than likely what was causing the problems. Now I needed to figure out why.

So I tried to think back through any changes I'd recently made to my computer that would cause a change in my CPU performance, and all I could come up with is that about two months ago, one of the cooling fans started running really loud, so I just unplugged it. Mind you, this is a laptop (HP ZD7000 w/a pentium 4 @ 3.06GHz), so this probably could easily build up too much heat. After this the temperatures weren't getting high enough to trip the high temp shutdown, so I just left it unplugged.

So, I downloaded CPUID HWMonitor and looked at the temperature of my CPU, as well as the processor usage in the task manager while streaming a movie. Low and behold the video began to get choppy right when the CPU started to hover over 90% usage. What was more interesting is that these two things could be directly correlated to a threshold temperature of 66C. <65C everything was fine, >65C no good.

Last night I bought a Cooler Master Laptop cooler for $12, and watched a movie. CPU temps stayed at around 62C or less, and the video playback was flawless. So I don't really have a problem at this point, but I was curious if anyone knew whether this is a normal function of CPU's. I knew high temps could damage processors, but I didn't know they'd cause loss of performance.

So CPUs (I know new ones do) throttle back the CPS speed when a set temperatures is reached. I would REPLACE that fan, it could also be providing cooling to other Parts of the computer, ie the IGP, the mosfets.