CPU still too hot after installing new heatsink and fan

slothnstein

Distinguished
Mar 27, 2006
5
0
18,510
So my computer began crashing while playing games. I figured out that the CPU temperature was extremely high. At idle, it would float around 70C. I've had the same stock heatsink and fan on top of my CPU for a long time. So I decided it was time for an upgrade. I bought a Zalman CNPS9500 fan and heatsink. I installed it properly and it only dropped my temperature just a little bit. It now idles around 60C. My computer is in a well ventilated area with a good case fan as well. What other issues besides the CPU fan and heatsink could cause the temperature to be so high? Could it be a bad power supply?

I have an AMD Phenom 9850 Quad-Core 2.5 GHz. and an Antec 500W power supply.
 

suteck

Distinguished
Are you overclocking? Raised the cpu vcore for any reason? What it the ambient temp in the room? I think Dadiggle hit it on the head with the thermal paste though. What brand did you use and did you apply it correctly - thoroughly, drying/curing time and all?
 

madbrit

Distinguished
Jan 12, 2011
29
0
18,530
I had this, turned out to be the heat sync was not dead flat on the CPU, with some systems it can be screwed down very slightly off, as mentioned already, you must clean ALL old paste off to a near polish, and use a good paste, but not too thick as this can lead to a nasty gap. Not an expert just from experience
 

hobbesmarcus

Honorable
Mar 15, 2013
21
0
10,510

Madbrit thank you so, so much. My old fan was buzzing and slowly dying as it was nearly six years old. I got a new heatsink and fan, installed it and somehow my CPU temperature went up by about 20°C. I just about went crazy trying to figure out what was wrong. Then I searched and found your post and remembered I hadn't screwed the heatsink in as much as I could have when I was trying to put the fan on to ensure the fan fit. I opened up my case, screwed the heatsink in as much as it could go and boom, temperature dropped by about 22°C. Many thanks for your post!

It's been over two years since you made that post but I'm hoping you'll still read this to know how much you helped me out :)