Bad case airflow or...?

[AMDThunder]

Was getting an odd noise from my PC yesterday. Thought it was maybe a fan going bad, so I pulled the side off to have a look. Turned out to be vibration in my case. Just moved it a hair and it went away.

K, now to the point. Thought I'd check my temps with the side off just for shits and giggles. I was surprised to see my temps were down a full 5C. I'm assuming this is an airflow issue. I have an Antec SohoII server tower, so there's plenty of room inside. Wiring isn't bad, as I have all the unused ones tucked away. 2 80mm fans in front blowing in, and 2 80mm fans blowing out the ass end. The fans are about 4 years old, and I was thinking of replacing them anyway.

I'd always been under the impression that having the case closed up actually provided for better airflow. I've left the side off for now as it isn't really much louder than with it on.

One minor detail: one of the pci cover plates is missing on the back, but I wouldn't think that would be a big deal.

Any idea or suggestions? I can probably post a pic of the case and stuff if someone can recommend a good site to post em.

Thanks!

 

[John_C]

Yep. Any time it is cooler with the side off, that's a sure sign of bad airflow. The SOHO II is an "older" design where heat from the video card can easily get trapped at the bottom of the case. I don't know if that's the problem, but it seems reasonable that its a contributor. Also, check the cables and make sure you don't have ribbons blocking your air flow. I don't suspect replacing the fans will do much good. Personally, I'd play with the wires a bit while it is open anyway and then replace the case whenever I did my next build but I would not worry about it until then unless I was seeing some type of actual problems resulting from the additional heat.

 

[AMDThunder]

Thanks for the reply!

Well I bought the case at least 4 years ago, so "older" fits the bill. One of my front fans is at the bottom of the case, with the other front one right above it in the extra HDD cage. You'd think that might overcome any extra heat at the bottom. Main reason I considered replacing the fans is cuz they were purchased when I got the case. Thought maybe they weren't pushing air as good as when they were new. They're Antec fans that prolly cost me $10-15 for all four.

The one ribbon cable does go across the air path, but it's pretty much sideways, so it shouldn't be too restrictive. Wonder if I can find a longer ribbon cable where I could tuck the excess out of the way.

Any ideas for better fan placement? I know that's fairly restricted anyway, but I'd thought about moving the top fan up a notch to the next HDD cage to blow air straight across to the exhaust fans. They're kind of offset currently. Should I move them both up? If I do that, should I have them blow over the HDDs, or move the HDDs down to the lower cage? (Which will require a longer ribbon cable anyway. Can't reach both my CD burner and 2nd HDD in that setup.) That may also get a little more air moving over the CPU.

I seem to remember reading about fans that install somehow in the pci slot area. Anyone know anything about that? Or am I smoking crack, and that doesn't exist?

Temps aren't really high (54/55 idle with case closed), but if I can get em lower, might push for 3.2.

Thanks again!

 

[John_C]

Even with an intake fan at the bottom, there isn't any place for the air to go down at the bottom of the case. The slot fans you mention are potentially your best bet (hard to know for sure since all of this is just speculation regarding what is actually going on). But that would give you an exhaust in that area. Best of all, they are cheap so it won't cost much to experiment. ( http://www.newegg.com/Product/Product.asp?Item=N82E16811999154 ) Before doing anything though, I might just remove a couple of the little card slot filler blanks below your video card just to see if the front fan might be able to create some airflow and to see if it makes any difference. Generally speaking these types of issues are best addressed through trial and error.

 

[AMDThunder]

Thanks a ton for your input. I'll pop out a couple more of the slot covers tonight to see if it helps out. I'm really thinking moving one of those front fans up higher may help as well. Just need to find a longer ribbon cable. The one drawback to the S3 mobo, the IDE connecter is at the bottom of the board. Guess I could pony up for a SATA dvd drive and solve the problem.

 

[harty23690]

rounded IDE cable?

 

[AMDThunder]

Well, I removed the pci slot fillers in the back to no avail. Temps stay the same with the case closed. Haven't had a chance to move my fans around yet. Too much static flying around the house right now.

A question about fans. While I'm still considering moving one up to get air blowing from one intake fan directly across to the exhaust, is there any way to know exactly how much air the fans should be pushing? I know that's prolly pretty subjective, but it doesn't feel like my intake fans are pushing much air. While I do have a fairly large case, if I place my hand around the middle of the case, directly in the path my lower intake fan, I can barely feel any air at all. The fans seem to be spinning fine, and are set on max. Is this normal for an 80mm fan?

As I mentioned before, the fans are roughly 4 years old, and been running on max the whole time. Not 24/7 though, as I shut down my pc at night. Just not sure if they can lose their effectiveness over time.

 

[John_C]

Let's try something radical... why don't you try unplugging the top intake fan on the front and see what happens. Without the ability to really see what is happening, sometimes this can become old fashioned trial and error.

Fans are cheap. You can certainly replace them. But I think the likelihood of that being your problem is pretty small.

 

[AMDThunder]

Sorry for the delay, but it took me a while to find time to mess with my PC. I unplugged both of the front fans, and think I found my culprit. No temp change at all with front fans disconnected. Was actually a dregee or 2 cooler with the side off.

I'm guessing either the fans are going south, or there's a ton of dust somewhere I can't reach. Front face doesn't come off easy, but I guess that's my next step.

 

[nioin3k]

I'm too lazy to read all of the posts, but, an old system most likely has quite a bit of dust, depending on how well you take care of it. My opinion is take all the hardware and fans out, clean that sucker out and if there's some dust in there it'll definitely help to clear it out.

Also 4 year old fans are probably bad news, if you can, upgrade to bigger ones, fans are very cheap to buy.

 

[AMDThunder]

New system, old case. Cleaned it out best I could before rebuilding. Just couldn't get the front panel off. Will have to get it off to figure out if I need new fans, or just a little more diligent cleaning.

And really, 8 posts isn't that much to read.