Computer Cooling

Spinning Hat · Post by **Spinning Hat** » Wed Aug 16, 2006 12:53 am

Ok, so as you all may or may not be aware, I've been having cooling issues with my PC this summer. (It is, afterall, my first summer with this sucker, as it's not even a year old yet.) Over the last winter and spring, the temps in the case were around 30 degrees C for ambient and CPU temps, while the GPU was slightly higher. (Normally 2-6 degrees or so.) This summer we haven't been running the air all the time, but do when it is forecast to be 85+.

Fast forward to when we turned the air off two weeks ago: Ambient Temps average 44 degrees C, GPU Idles at 58, while the CPU is around 40 or so. Up until last night, the temps are all about 8 - 10 degrees warmer, until I took one of these: Vantec Stealth 120mm case fan. I liked it because it was quiet, and seemed to move air fairly well. I removed it, and replaced it with 2 of the Flashing red LED fans I got from the las Mega LAN we had in dallas. That's when I saw a drop.

So I figure, hey,. now's a good time to see if the temps inside the case have dropped enough to Play WoW or T2 without the artifacts and the pesky locking up.... No Dice. T2 locked up in the course of 1.5 maps, and WoW had artifacts like you wouldn't believe.. I thought I had taken something for a while there, but turned out, if I looked away from the monitor my vision returned to normal. (...Drat!)

I have a clock that has a thermometer on it, and the temp downstairs is a warm, but not too hot 78 degrees.... So, being the proactive kind of guy I am, I sauntered over to Newegg, and started looking for new case fans to increase the airflow inside, but not necessarily increase the noise that emenates from my case. I found two likely candidates there, and I even checked TigerDirect for good measure, and they didn't have near the selection of Newegg. Here's what I ordered this morning:
2 Thermaltake Thunderblade 120mm blue LED fans and 1 Thermaltake 80mm Blue LED Smartfan.

The original 80mm fan I have in my case is the blue LED fan that came with it, so I can only assume that it's not a great fan for conducting air and it's there to look pretty.

So my question is this: What do you guys do to keep your systems cool without resorting to Water Cooling? And, do you always have to sacrifice airflow for sound? I found this fan that moves more than the Thermaltake fans, but I really didn't want something that loud.

Post by **XMEN Gambit** » Wed Aug 16, 2006 6:11 pm

Noise is a result of not enough sound insulation and high rpms. So to reduce noise, you could get a bigger, slower fan that would have the same CFM, or insulate your fan mountings with rubber washers/grommets, etc.

I'm suspicious of your whole overheating issue, though. How is it with the side of the case off?

Ambush Bug · Post by **Ambush Bug** » Wed Aug 16, 2006 7:48 pm

Ho ho ho, the fun stuff!

First off, bigger fans move more air, and do it at a lower RPM, which in turn leads to less noise. If you have the holes in the case for 120mm fans... stick with 120mm fans.

Second is airflow, and there are different ways to arrange it. You can:

...go the OEM route. That means in from the front-bottom, out from the top back, emphasis on quiet. This usually involves one intake fan and the PSU exhaust fan. I am not fond of this method.

...go for the ducted route. This is usually cutting a hole in the side of your case, mounting a big powerful fan sucking in, and putting a duct around it that leads to the top of the CPU heatsink. Fans can be anything from your average 120mm fan to a full-bore squirrel-cager.

...go for the OEM+duct route. This requires a lot of ductwork to get the air from your intake fans over the CPU, with ductwork to handle the exhaust as well, through a dedicated hole. Rackmount servers did this a lot back in the day. This method works well, but can be complex to set up.

...go the au natural route. Route your cables out of the way, make a clear path, and arrange fans for positive pressure, take advantage of the natural properties of hot air, and enjoy the quiet.

No matter what method you use, though, you have to consider that heat is going to rise. Find out which components generate a lot of heat, map out where they are on your board, and adjust the airflow and ducting to take advantage of that fact.

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Other things: positive case pressure is good. If your intake is powerful enough, and your exhaust ports are controlled//few in number, you will have a slight overpressure in the case. This is good, as it means all the dust and crap that comes through the intake will only come in through the intake, and you can filter that out.

Sound isolation: One of the best things you can do to help with noise is to mount the fans on rubber grommets. Use 'em like washers so that no part of the metal screw actually touches any part of the mounting hole, only the grommets. This will cut down on vibration transmitted to the case, but it won't do a whole bunch for harmonic resonation. For that you need to change the properties of the case-panel itself, and that involves stuff like putting strips of duct tape or insulating foam on it.

Grommets are also handy for hard drives, if you can make them fit. I've seen setups where folks will actually suspend the drive in the middle of a 5.25" bay with flexible rubber tubing.

Interior airflow: You can make ducts out of cardboard cereal boxes and, er, duct tape. Really easy to do. Worth a try.

Don't forget that any cables you've got hanging about will impede airflow as well. Use SATA if you've got it, if not, fold and route your ribbon cables out of the airflow path. I'm not very much a fan of rounded IDE cables, and will not use them. (This is because I like to keep my materials in-spec)

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If you don't mind spending a bit of money, you can replace heatsinks and their associated fans with bolt-on units from a third party. Zalman, in particular, is well-known for making very, very quiet sinks and heatsink+fan units. Only caveat with Zalman stuff is that it's usually big, and can be troublesome to fit inside your case if it's cramped.

How about some pictures of your case and its interior layout, Hat? That'd be helpful.

Spinning Hat · Post by **Spinning Hat** » Thu Aug 17, 2006 12:51 am

AB - I'll work on the pics... I prefer the Au Natural route when it comes to cooling, mostly because it's a little more elegant, and that's what I've started with here already, as most all the cables are tied / wrapped / wrangled out of the way of the airflow stream.

Gambit - I haven't tried to run it with the side off yet, but I'll try it. My PSU has 3 fans on it, and they are adjustable, and they're running on full steam right now, just trying to evacuate the hot air out of the case. I really wish at this point that my case has mounting holes for a 120mm fan on the side, as that would help the overpressure a bit, and that would indeed be nice. I don't think my 3 80mm fans can supply enough air to keep up with the 1 120mm fan and the 3 80mm fans in the PSU...

Spinning Hat · Post by **Spinning Hat** » Thu Aug 17, 2006 1:12 am

So I took the side of my case off, and the temp appears to be on the downward trend, but it's only been about 15 minutes since I took it off, so I'm going to let it run for a while, and overnight, and see if it does continue down, or if all I get is a 1 degree drop.

Spinning Hat · Post by **Spinning Hat** » Thu Aug 17, 2006 1:41 am

Frustrations continue.... SO I rebooted and looked at what the BIOS qwas saying about the temps, and it was saying the CPU was idling happily at 34 degrees celcius, while the Chipset temp (mobo temp) was at a warmer 44 degrees, which is what agrees with Asus Probe, and the Nvidia temp monitor. It seems so far, that there's not going to be a significant temperature decrease by leaving the case side off all night. When you put your hand just inside the case, the air inside feels cooler than that of the air outside the case, but I'm not seeing a temperature decrese at all....

XMEN Iceman · Post by **XMEN Iceman** » Thu Aug 17, 2006 9:21 am

You have something really bizarre going on. What are you using as the thermal compound on the CPU? Arctic Silver?

I am beginning to think you have an air gap there on the CPU. Make sure when you apply thermal compounds that it is the thinnest you can make it without scraping it off...too much compound actually insulates and overheats CPU's sometimes.

Just a thought.

Spinning Hat · Post by **Spinning Hat** » Thu Aug 17, 2006 11:55 am

The CPU is not the problem. the GPU is the problem. I've got the Retail heatsink/fan that came with my chip, (I always buy the retail ones..) and that's been running exceptionally cool in regards to the GPU and chipset temps.

And I left the side of the case off all night, and the gpu temp dropped about 2 degrees in 8 hours.. not a real big change...

Ambush Bug · Post by **Ambush Bug** » Thu Aug 17, 2006 1:02 pm

If you want to check a 'no sidepanel' setup, I heartily recommend putting a box fan next to the computer and blasting the whole insides with it. Nothing you can mount on a case (excepting a bolt-on squirrel-cage) will outdo a box fan for sheer volume of air.

Two things come to mind:

1) What's mounted in the slots under your video card, relative to the floor of the room? And is the fan for the card on top or on bottom (also relative to the floor)?

2) Dust? It's a great insulator.

XMEN Iceman · Post by **XMEN Iceman** » Thu Aug 17, 2006 3:04 pm

Unless you are overclocking the vid card I see no reason for it to overheat...that is just plain weird. I mean most vid cards can run 150+ degrees and not budge I would expect. They are made to run hot and handle it. Unless the heatsink is not secure to the chip.

Post by **XMEN Gambit** » Thu Aug 17, 2006 6:01 pm

XMEN Iceman wrote:Unless the heatsink is not secure to the chip.

ding ding

Also check the RAM on the graphics card, and/or heatsink on those.

Spinning Hat · Post by **Spinning Hat** » Thu Aug 17, 2006 11:03 pm

The only thing mounted under the Vid card is my wireless netowrking card, and since my board is an SLI board, it's quite a bit away. I cleaned out all the dust when I took out my 120mm fan. And the fan for the card is on the bottom of the card. It's got this massive 5lb copper heatsink on it that covers the GPU and video RAM, and a good portion of the rest of the card. I'll shut down here in a few and see if the heatsink has come loose.. It's very likely with the size of this monster...

Here's apic of the "bottom" of the card with the fan and the heatsink attached to it:

Spinning Hat · Post by **Spinning Hat** » Fri Aug 18, 2006 1:35 am

Ok, so y'all don't think I'm totally off my rocker, here's a screen print of my temp readings from PC Probe and the Nvidia display properties...My Temps Beware, it's a full size image, at 1280 x 1024, but it's a jpeg.

Post by **XMEN Gambit** » Fri Aug 18, 2006 4:52 pm

Yowza. Ya, let us know about the cooler on the GPU. You may need to pull it, clean it, and apply some nice heatsink compound. Preferably something non-conductive, which leaves out Arctic Silver. Still, good white goop oughta provide better results than a FREAKING 14C DIFFERENTIAL between GPU and ambient.

Gah.

Spinning Hat · Post by **Spinning Hat** » Sat Aug 19, 2006 1:32 am

I can't take the heatsink off... it's got some special fasteners on it, and I don't have the tools to remove them without wrecking something.. I've got the RMA request in, we'll just see what Leadtek has to say.