AMD processors have a pretty good reputation as being relatively cool. This doesn't negate the need for large air coolers, but it does allow for quieter setups if that's what the user chooses. In my personal HTPC, Zalman CNPS9500 LED doesn't even turn it's fan on until the Athlon 64 3500+ hits 38°C, which it does occasionally, but not all the time.
The Zalman CNPS9500 AM2 (provided by our buds at ) we'll be looking at today doesn't change the formula all that much from their previous CNPS9500. In fact, it's the same cooler except it's AMD only, but with a new clip designed specifically for the AM2. NVIDIA was showing these off at a press event a few months back, and while we didn't get much in the way of numbers back then, today we will.
The Zalman CNPS9500 AM2 Heatsink
The Zalman CNPS9500 AM2 has the same orb shape we're familiar with as their other coolers. The CNPS9500 AM2 is very large, measuring 85(L) x 112(W) x 125(H)mm, which is the same as their previous CNPS9500. It does stand fairly high and provided you install it properly, it should not interfere with components such as ram or North Bridge coolers provided the motherboard maker follows AMD's specifications. It will cause problems with some cases though, especially ones with fan ducts. This was an issue we've experienced with previous Zalman coolers, as well as any cooler taller than 80mm. Officially, Zalman states that cases should have a clearance of 135mm away from the motherboard. Video cards and PSUs should be 56mm from the center of the CPU, and memory should be 45mm from the center of the CPU.
We didn't count them, but there are a large number of 0.2mm thick fins which equates to a large surface area for heat dissipation (3,698 cm2 according to specifications). The fins are arranged in an aerodynamically optimized tunnel design, which maximizes airflow contact from the fan. The entire package, save for the fan and mounting tools of course, is constructed entirely out of copper (with pretty slick chrome plating) and weighs in at a hefty 530g. While heavy, it should not cause any problems due to weight.
The 92mm fan is of the LED variety and has a soft green glow when powered on. Since the cooler is endorsed by NVIDIA, this explains the colour choice. As with many of Zalman's coolers, this fan is near silent at the lowest fan setting (1350 rpm/18dB). This is provided you use the included rheostat to control the fan speed. At high speed (2600 rpm/27.5dB), the Zalman CNPS9500 is quite audible. This only happens under heavy load though as the cooler was much quieter than the video card fan during regular use.
Zalman uses a patented heat pipe bending design heat pipe design which consists of 3 pipes, but the inverted design creates a heat transfer capacity equivalent to 6 heat pipes. All these pipes connect to the base, which is machined very flat, though not to a mirror finish.
There are a few fan accessories included in the package, such as an adjustable fan speed controller (FAN MATE 2), mounting tools and manual. Tools for the installation of AMD based CPUs (such as Opteron, Athlon 64 X2 Dual-Core, Athlon 64 FX, Athlon 64, Sempron for Socket AM2/754/939/940) setups are included. Other extras include a small tube of thermal paste and a case badge.
Installation is incredibly easy, as no motherboard or retention bracket removal is required on AM2 setups. The most complicated step is sliding the retention mechanism through the heatpipes. Once that is done, slide the retaining clip and anchor it on to the motherboard. If you're using an aftermarket cooler that has its own custom retention bracket, you may or may not have to put in a little more elbow grease to remove it.
MSI K9N Platinum: AMD AM2 4400+, 2 x 512MB Corsair TWINX PC6400, MSI NX7900GT, 160GB Seagate SATA 7200.7.
ASUS A8N32-SLI: AMD Socket 3000+, 2 x 512MB Corsair TWINX PC6400, MSI NX7900GT, 160GB Seagate SATA 7200.7.
AMD includes a pretty nice heatsink with their retail packages of AM2 processors, but since ours is an OEM processor, we do not have a stock cooler. Therefore, our results will only be of the CNPS9500 AM2. We did include a retail 3000+ since the Zalman is compatible.
Prime95 was run for nine hours, with Folding @ Home running in the background everyday for four days to load the system and allow the thermal paste to even out. During the actual tests, we ran SiSoft Sandra's CPU Burn for 15 minutes, with Folding @ Home running in the background. Ambient room temperature was maintained at 23°C/74°F.
Temperatures are going to be very low when the PC isn't doing anything. Interesting to see that the Zalman CNPS9500 on the AM2 is only 1°C warmer than an Athlon 3000+ using a stock AVC cooler.
The Zalman CNPS9500 AM2 keeps the AM2 4400+ under 50°C, and only a couple more degrees warmer than the much slower 3000+ with the stock cooler. The Zalman is about the same in terms of noise at it's highest fan settings to our ears, but under normal usage, it's noticeably quieter.
It's tough to gauge exactly where this cooler stands among the rest since this is our first AM2 cooler, but the performance with the Zalman CNPS9500 AM2 was very good. The key thing we were pleased with was the ease of installation. Provided you have a stock AM2 motherboard configuration, it should literally take you less than 3 minutes to change coolers, and under 2 minutes to install the Zalman from scratch.
We didn't see huge improvements over the stock cooler for the Athlon 64 3000+, but I think that is due to the fact that the CPU runs so cool to begin with. From what we've seen with the CNPS9500 LED, with a hotter processor, the gap between the Zalman and stock cooler will increase.
The CMPS9500 AM2 was very quiet throughout testing. It spun up to it's maximum speed once it hit full load, but it took over 3 minutes to do that. Basically, if you tend to load up your CPU in short bursts, the cooler may never hit full speed. To be honest, I'm not really sure of any real-world examples of that, but in day-to-day use, it will not be very disturbing. I did email another editor who has reviewed this cooler and was told that it performs about 4°C to 5°C better than the stock cooler, but is significantly quieter.
The only issue we see with the CNPS9500 AM2 is the size may be prohibitive for some user's setups. We provided the numbers earlier in the review and so long as your system meets the clearance requirements, you should be fine. Of course, this cooler will do no good if you're an Intel user, but the CNPS9500 LED works fine for you there. The Zalman CNPS9500 AM2 is out there, but we feel the combination of low noise, good performance and extreme ease of use make it a worthwhile consideration.
Thanks to our sponsors at for making this review possible.
If you have any comments, be sure to hit us up in our forums.