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View Full Version : Xtra Fans, Do they help?



JJJJJ
13-01-2005, 02:16 PM
I notice, today being rather warm, my CPU temp has got up to 42. M/B 35.
How much of a drop could I expect if I installed another fan. I have the hole in my case to fit one.
At present I just have a CPU fan and of course the one on the PSU

I have an automatic fan speed- up which is still running in slow mode. The default speed up temp is 55.

How are fans measured? My vacant fan hole has mounting screw holes about 3 1/4 inches apart. My ruler doesn't do metric. Would that be for a 90 mm.fan?
Jack

Speedy Gonzales
13-01-2005, 02:28 PM
Most fans are either 80mm or 120mm the fan size just above 80mm.

Some cases have the cutout/template for either 80mm or 120mm fans.

FoxyMX
13-01-2005, 03:57 PM
Should have got an Intel, Jack. My CPU is only 26C in this lovely hot 30C room today. :p

Mmmm.... summer at last. :D

agent
13-01-2005, 04:10 PM
Anyone who is a fan of Xtra should be shot on sight. They don't do anything to help the crusade against ridiculous prices.

Graham L
13-01-2005, 04:22 PM
Your CPU is at 26 deg C in a 30 deg ambient, Foxy Susan?

Unless you have a Peltier cooling plate on it, the sensor is telling you lies.

FoxyMX
13-01-2005, 04:33 PM
You're telling me that AIDA is telling me lies, Graham?! Surely not...? :eek: :p


Hmm... the motherboard temp is 29C - how can that be hotter than the CPU? :rolleyes:

:D

robsonde
13-01-2005, 07:10 PM
the temp sensor on the motherboard and CPU is made as cheep as they can.

often they can be out by as much a 5C

JJJJJ
13-01-2005, 07:43 PM
Just as a point of interest. Asusprobe gave my CPU temp at 42. Everest said 42. My bios said 41. And SiSoft Sandra said 39. To be on the safe side I believe in the highest one.

Nobody answered my question. What sort of a reduction can I expect if I install a n extra fan?

Jack

Prescott
13-01-2005, 07:52 PM
depends how many and how big , you need lots of air FLOW through the case not jut fans that blow onto the cpu. 42C isnt that hot so you shouldnt be worried. with an extra fan maybe 5-8C??

PaulD
13-01-2005, 07:54 PM
If the room temp was anything close to the MB temp, any extra fan wouldn't make much difference. CPU temps in the 40s with the fan on slow are nothing to worry about. If your CPU fan was running at full speed for long periods, that might be worth looking at again. The latest AMD run cooler than previous Athlons.

Prescott
13-01-2005, 08:03 PM
reading from JJJJJ's first post he only has 1 fan, that is the cpu, and a hole at the back so he doesnt really have air flow, why dont you try, 80mm fans are dirt cheap these days

theother1
13-01-2005, 10:15 PM
Jack, it definitely sounds like a new motherboard is what you need. :thumbs:

Metla
13-01-2005, 10:51 PM
reading from JJJJJ's first post he only has 1 fan, that is the cpu, and a hole at the back so he doesnt really have air flow, why dont you try, 80mm fans are dirt cheap these days

The airflow is created by the fan in the powersupply sucking air out of the case,which causes fresh air to be drawn in the front of the case,over the HD,motherboard,ram,etc etc

A case fan may help by a few degrees,But wont cure a badly laid out system......

FoxyMX
14-01-2005, 08:29 AM
Jack, it definitely sounds like a new motherboard is what you need. :thumbs:
LMAO :D

Poor Jack, he's never going to live that one down. :p

JJJJJ
14-01-2005, 09:03 AM
LMAO :D

Poor Jack, he's never going to live that one down. :p

For your info I have Successfully installed a new mother board and strange as it may seem it works perfectly.
Jack

chiefnz
14-01-2005, 09:23 AM
To increase the airflow you should install a 120mm fan in the front of your case, most cases have a pre-cut hole for the fan. Just check to see that you case actually allows air to be sucked in from the front. My case had the hole for the fan but the plastic casing covering the actual metal chassis didn't, so I ended up drilling holes into the plastic casing to allow the air through.

MY CPU is overclocked by 600Mhz and before I had the fan in the front, the CPU temp was usually around 47-49 degrees, the motherboard temperature was round about 44- 46 degrees. Now I usually average 39-42 degrees for the CPU and 37-39 for the mobo. It gets up to 47-49 when I'm playing Doom3 or HL2 but it doesn't take long for the temp to go back down again.

I also have another fan at the rear of my case which extracts air.

The basic rule is to make sure that air is drawn into the case and then extracted out of it again. Essentially you want an airflow direction of FRONT TO BACK.

Hope that helps

cheers

chiefnz

theother1
14-01-2005, 09:37 AM
For your info I have Successfully installed a new mother board and strange as it may seem it works perfectly.
Jack

Jack, we know about that and applaud your tenacity, just kidding mate!
Rob's Home computer repairs. :badpc:

PaulD
14-01-2005, 09:38 AM
MY CPU is overclocked by 600Mhz and before I had the fan in the front, the CPU temp was usually around 47-49 degrees, the motherboard temperature was round about 44- 46 degrees. Now I usually average 39-42 degrees for the CPU and 37-39 for the mobo. It gets up to 47-49 when I'm playing Doom3 or HL2 but it doesn't take long for the temp to go back down again.



Did you actually have any heat related problems before adding the extra fan? Or was it a peace of mind thing? Temp readings aren't very accurate. Some motherboard manufacturers have altered their bioses to reduce apparently high reported temps when there weren't any actual problems occurring. Real temps below 60 on load shouldn't be a problem.

Graham L
14-01-2005, 11:11 AM
Susan, as long as you don't use refrigeration (such as a Peltier element) the case of the CPU can never get cooler than the air around it. Ever. The CPU chip can't get cooler than the package it's in. Ever. Hotter, yes. This can be a problem.

It's to do with the second law of thermodynamics. That's been the dowbnfall of many "clever" ideas.

AIDA or any other programme whuch reports temperatures is only a programme. IT only knows what it has been told. It makes a calculation based on the number it gets from the sensor. Sensors are cheap. To be cheap they are not make to close tolerances. You have to calibrate them before you can trust the measurements.

I have been playing with a very clever little temperature sensor. It gives 12 bit output, with resolution to 1/16 of a degree. Without special adjustments it's accurate to 1/2 degree. A wonderful little device. It can give alarms when it sees temperatures above or below limits you set.

But the manufacturers had a problem with batch B7. These units can randomly change their calibration numbers when they are powered up. After that, they can be wrong by up to 20 degrees. So to use them, you have to be very careful. You read the calibration constants the first time you use them. Then, each time, youi have to load the saved values into the unit.

You can't trust measurements.

When a device which is using 30 or 40 watts of power is said to be even 4 degrees cooler than the air around it, the measurement is WRONG.

chiefnz
14-01-2005, 11:18 AM
Did you actually have any heat related problems before adding the extra fan? Or was it a peace of mind thing? Temp readings aren't very accurate. Some motherboard manufacturers have altered their bioses to reduce apparently high reported temps when there weren't any actual problems occurring. Real temps below 60 on load shouldn't be a problem.

No I didn't have any problems, but after all the research I did on how far my CPU could be over-clocked, I thought it best to add the extra fans.

cheers

chiefnz