Cooler Master Seidon 240M - All-In-One CPU Liquid Water Cooling System with 240mm Radiator and 2 Fans

Pros: Easy installation, great cooling solution, good build quality, the pump is pretty quiet.

Cons: Included fans are noisy.

Overall Review: I started looking heavily into overclocking recently. My old i5 2500 could overclock decently with the stock air cooler, but my i5 4670k was burning up at 75-80C core temps! And it could barely go past 4.4GHz. After a friend of mine told me the wonders of liquid cooling, I decided to get this kit. Installation is a breeze and works well with the Rosewill Thor V2 case. The included fans are noisy though- they're 4 PIN fans and I think I may lower the fan speed to quiet them down. My core temps idle at 30C and at load 45-50C which is significantly better than 75C! With the stock fan it was idling at 44C. I highly recommend this to anyone on the fence about liquid cooling.

Pros: - AIO cooling system. No replacing coolant or external pumps and so far it's lasted. At 1+ years and not leaking I'd consider it a worthwhile investment. - Affordable. (Mine was purchased on sale for $55.) - Cool temps. I've seen 11C idle and 34C under a long night of gaming with mid-40's under heavy load. (AMD FX-8350 @ 4.2GHz) [see OTs] - Intel or AMD. - Quiet mostly [see cons.] - The tubes connecting the radiator to the CPU pump are very firm and nearly impossible to pinch or obscure the flow of liquid throughout the device. - The tubes between the radiator and the CPU pump are rather stiff and not so malleable. This shouldn't be an issue unless you plan to put the radiator face-down and an inch or two from the radiator...which should practically never be a scenario...

Cons: I have a massive Cooler Master case so this isn't much of a problem for me but the radiator is actually kind of bulky. I could see it being an issue with smaller cases. But this cooler is obviously not practical for a micro build or anything. So any larger mid-ATX is preferred. I had heard some liquid noises before but lately they haven't been apparent. It sounded like you could hear liquid moving around the tubes. Air bubbles? This may also have been commensurate with the issue outlined in the OT's below. Somewhere between relocating the radiator and replacing the case siding fixed my temperature issue.

Overall Review: AIO coolers are a great budget way of water cooling and are a great option for a 'bang for your buck' build. Consider, however, that they may only be half of the battle. Once I had the side of my case ajar while I was tinkering and was too lazy to put it back together. When I encoded a video my temps shot to dangerous levels and caused system instability in both Windows 7/8 and Linux. I was baffled. I relocated the radiator to another fan spot on my case and, with the side of the case off, still had the same result. Finally, figuring my cooler had reached the EOL I gave up, reattached my case, and began to research another CPU cooler to upgrade to. I decided to run a stress test again to see if there was still a problem and lo' and behold there was not! Lesson learned. Keep your case together and air flow consistent and this cooler will continue to shine. As mentioned in cons I also had heard liquid noises of water being circulated around the tubes. I'm just now noticing I haven't heard that noise since I was having temperature problems. So those could go hand in hand. Additional note: I have a budget Gigabyte 990FXA UD3 motherboard which gives improper temperature readings. I was confused for the longest time as AMD Overdrive read 40C at idle and 70C+ under load. As it turns out, these motherboards are notoriously bugged with temp readings and you have to download the free program HWmonitor to get accurate readings. Case: COOLER MASTER RC-692-KKN2 CM690 with 4x 120mm fans and 1x 60mm fan. CPU: AMD FX-8350 @ 4.2GHz

Pros: Assured fit with the Coolermaster HAF XM tower for my new build. Bolted right up no problem and attaching the giant copper heat plate to my MB was a breeze. My first watercooled rig. Small socket provided to assist in attachment of the Cooler standoffs. Prefilled Price was right with a rebate compared to the higher end air coolers I looked over.

Cons: I'll always worry about the possibility of a leak. In some circumstances you might want a cooler where you can route lines thru a case and have to fill it with coolant later. This cooler being fully assembled means you don't have a whole lot of play in positioning.

Overall Review: my i5 is always running too hot since it's oc'd to the danger zone most of the time. This cooler could absorb anything I tossed at it and CPU temp rarely hit 50. Easier to clean then a straight CPU cooler as the radiator is accessible from the top panel of the case. Nice setup. I have cats and fur has always been a problem, it seems to get in everything. The air cooler for my i5 needs monthly dust off treatments. We'll see how much ends up in the radiator.

Pros: Quiet Efficient Cheap Easy to install

Cons: Tubing a little stiff

Overall Review: Bought to replace a stock Intel cooler on a Haswell cpu that is run at stock. All I needed was cheap AIO cooler and this has been excellent. Fits in to a mid tower case, cools well 56C full load (prime 95) and is reasonably quiet. Certainly it is quieter that the stock hsf and keeps the cpu 20C cooler.

Pros: Good construction feel and great packaging. I'm not sure why some of the reviews down the instructions. I found them to be adequate. Installation was much easier than I expected and everything fit very nicely. On my i7-930 I got high 30's at idle and no higher than mid 60's at full load at stock clock with HT and Turbo boost enabled. This is with a push pull configuration. I assume it'd be better with fans optimized for static pressure. With the stock fan and the silenx fan I have on it, it is dead quiet! If you're looking for good budget cooling that doesn't take much space and is near silent, this is a wonderful product and a great alternative to the more popular closed loop water cooling solutions.

Cons: This is my first water cooling experience and like many, I worried about leaking. Sure enough it happened to me. After installing, I ran a video render that would push the cpu to see how it handles full load and everything seemed fine. I then played a game of LoL and roughly 10-15 minutes in, the game froze up and I had to restart. I smelled an odor coming from the case so I powered off the computer and popped open the case. Cooling fluid had dripped out of the return hose linkage onto my video card and got into the pci-e port. I then started the computer again to make sure it was still leaking and hit it with good ol prime95. There was no leaking until I started prime95 on default settings. Almost immediately, it began leaking at the same spot as mentioned previously. I took out the Seidon and put my stock cooler back on. I'm sure these are good coolers and most people considering going to water cooling probably had the same fears that I did. I'm just sad that I was one of the folks that had to experience it first hand. I can't give this anything more than 1 egg. I have good faith in Cooler Master products. I'm a big fan as my case is a from them and I had a TX3 air cooler on my older rig. I'm guessing I just happened to get one of the bad ones. I will be trying to RMA this or contacting Cooler Master directly and pray that my video card and/ or motherboard are fine.

Pros: Keeps my i7 930 cool. Very Quiet. Fit my 1366 motherboard. Fit my HAF 912 rear fan mount.

Cons: Missing instructions from my box; I had to go online to view the instructions and even then the instructions were somewhat lacking. Pump does produce some noise/buzzing but it is very minimal. I cannot hear it once I get more then 2 feet away from the case

Overall Review: I bought this cooler as a project to silence my PC. I was running multiple 80cm fans (running @ 100%) in a case that was 12 years old. I upgraded to a HAF case, some Noctua fans, and this watercooler (same hardware). Overall, my temps dropped and the the noise from the machine is now more then a 1/3rd what it was. A few things that need attention... the directions aren't great! They aren't horrible BUT they aren't great either. A few points that I feel should have been stressed were not. First, if this is your first watercooler install then don't do this install when your tired (like I did). This install (the first time) might take you up to 45 minutes. Speaking about the Intel-side, there are 4 standoffs provided; both sides of the stand offs are female. One side, which contacts the mobo, screws into the mobo backplate. NOTE: one side of the standoffs has a non-conductive black coating. This side MUST face down towards the mobo surface. Although this might seem obvious to most experience installers this might not even phase a novice. I felt the instructions didn't make that completely apparent. Finally, the kit comes with a socket-to-Phillips adapter to tighten down the standoffs to the backplate and mobo. If you read anything about my review, READ THIS...... DO NOT USE THIS TOOL. Why? Most people I know have a tendency to REALLY torque things. What does that mean? Possibly a dead mobo! The black non-conductive coating will tear and the standoff will start to shred your mobo and copper connectors causing shorts and/or broken paths. My advice, hand tighten the standoffs (but a good tight). When you tighten the pump mechanism to the standoffs the standoffs will tighten further. Again, don't torque it... hand tighten but this time using the philips screwdriver. When each standoff starts to turn then you're done! Any more and your asking for trouble. Overall, my temps did drop from the stock i7 cooler. The noise level is good although it needed some tweaking (via speedfan). I find the temps are much more stable especially when under load. So, I did have to use speedfan. Why? Because my mobo runs PWM fans at ~50-60% speed at idle. I used speedfan to drop the idle RPM's from ~1500 to ~600. The temps still stay under 40C even with some heavy Mysql operations running. Again, I was going for a VERY silent PC since I work from home and this PC sits right next to me. Before my project to silence the PC this thing sounded like a rack mount server. Now, I don't hear the fans over the pellet stove in the next room. I don't sleep in the room that this PC runs but I don't think I would have a problem doing. This cooler is quite when the RPM's are properly matched to the temperature. I give it 4 stars... minus one due to the bad(missing) instructions and the inclusion of a tool I feel is not necessary and is likely to kill many mobos

Pros: Performs way above expectations! My current setup was banging on ~60 degrees under load, 70+ degrees under load with some overclock. Now, I'm sitting at 47 degrees under load, and maybe 60-some degrees with the same overclock. CPU idles about 1-3 degrees above case temperature at best. My previous cooler wan an older Coolit ECO 120, basically the predecessor to all the Corsair AIO (all in one) 120mm units. It was great in it's day for my dual, quad, and even six core AMD CPUS, but the 8 core Vishera with overclock (voltage hog) was just too much to handle. Installation was a breeze on my system. I'm using the fans in a push configuration with the radiator mounted to the top of my Antec p280. Perfect fit, perfect setup. The instructions, oddly enough, aren't terrible. (FYI, some cases with dual 120mm have the fan spacing kinda funny. To verify this unit will fit, get two 120mm fans and place them right next to each other, touching, if all eight holes line up this will fit your case.) With PWM (pulse width modulation (4 pin)) fan control and target CPU temp set to 40 degrees on my motherboard the fans run ~600 rpm idle and ~1500-1800 under full load. Most fans are pretty quiet if relatively unobstructed and kept at or below 1200 rpms. (Keep in mind, they could ramp up to ~2400, but there is no need as the system dumps heat so well.) At 1500 rpms, around 50% PWM speed, fans are just a smidgen above audible, but not at all loud enough to be annoying in my opinion. It's hard to judge sound, but the best way I can explain it is to say when my central heat kicks on, it is louder than my computer. Some have questioned why Cooler Master included fans capable of 2400 rpm...because they are quite loud at those speeds, but I like the option just in case I want to goof around and really push some high voltage during a benchmark or two. At 2400 rpm, they are loud, but for stock or mild overclocks I doubt you will ever need them to run past 1400-1500 rpms. At that speed they are pretty tame. I set mine up with the pump's power drawing from my "system fan one" 3 pin header (and it set to 100% in BIOS). Then I used the two PWM fan to one PWM plug adapter (included with the unit) to plug the fans into my CPU's 4 pin fan header, as I have better control over the CPU fan speed on my system. I don't know what else to say, this thing works...well. I haven't gotten the opportunity to compare it against it's rival AIO water coolers...but I can't imagine them doing much (if any) better. This system is simple and effective. Provided your motherboard has half way decent PWM control on the CPU header, you simply don't need a USB interface along with more software to make it work.

Cons: I honestly have none. It's functioning exactly as advertised.

Overall Review: Wow! Cooler Master has knocked it out of the park with this one. I haven't been this impressed with a CPU cooler for a long, long time. For the record... AMD FX-8350 @ 4ghz-5ghz MSI 990FXA-GD80 4 4gb 1600 Patriot Vipers @ 1600mhz 2 MSI 7870s in Crossfire @ 5760x1080 Eyefinity 2 Mushkin Chronos 120gb SSDs 2 Western Digital 150gb Raptor Xs Antec 1200 Antec p280 etc...etc...etc... PS: Do me a favor. If you go with a (any) water cooling setup, get some sort of airflow to your Northbridge and Mosfet areas on your motherboard. When manufactured they expect a standard CPU air cooler giving them a nice breeze, with setups like these that doesn't always happen. I'm personally using a pair of 40mm fans that came with an old set of RAM to provide such a breeze. With a water cooler your entire system will run cooler, but you still have to take care of your motherboard's hot spots. W

Pros: Allows me to maintain a mid level overclock on a Haswell processor. Fairly easy to install. No noticeable pump noise. Comes with hardware for two fans.

Cons: Copper base plate has a rough finish The tubes are stiff and causes the pump and plate to slide off center when installing. See Other Thoughts...

Overall Review: It's the low-end AIO cooler for Cooler Master. I understand some things may not be top-notch. However, it's still a good cooler as-is for a mild over-clock. I also have the Seidon XL. I installed this 120V on a G3258 Pentium dual-core (54w) with the included fan in the pull position and a Corsair SP120 Quiet in the push position. I had worse temps at stock speed than the stock cooler (35C Idle, 65C Prime 95). I let it sit for a month while working on other projects. Today, I decided to see if I could improve the temps. I undid the screws and found the dot-in-the-middle method had only spread to the upper 3/4 of the processor. That was an Ah-ha! moment. When installing, the tubes push the pump and baseplate off center. I used the business card thin spread method to replace the thermal paste (using Artic Silver 5) I also polished the copper baseplate to a mirror-like finish with MAAS metal polish and cotton balls. I made sure the plate was centered and then tightened down the screws making sure to maintain center. I am happy to report that I have much better temps. At 23C Ambient, it kept the processor at stock speed at 40C during Prime 95. That was a 25C improvement. I then cranked the processor up to 4.3GHz and it kept it at 27C idle and 65C Prime 95. When installing, don't count on the baseplate to spread the paste evenly. Use the business card method. Make sure you have it centered as you tighten down the nuts; recheck it as necessary. If you have an hour to kill, polish the copper baseplate to remove the grooves.