Asus P5K Deluxe - Improving Northbridge Cooling

calebb

calebb

[H]F Junkie
Joined
Mar 26, 2000
Messages
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As a lot of people have noticed, the northbridge chipset on P35 motherboards gets pretty warm at higher FSB frequencies (at least on the Asus P5K Deluxe!). This issue is even more noticeable with an after market HSF: The Intel stock HSF blows air down over the CPU which then cools the fins on the chipset heatpipes. However, most aftermarket HSF units do not circulate air near over the chipset heatpipes.

Pertinent Specs
  • Lian-li v1200
  • Rear case fan pulling in fresh air
  • E6320 (7x multi) @ 426MHz FSB (3GHz), 1.375V
  • Tuniq Tower 120 w/ Silverstone FM-121 Fan @ 100%
  • Tuniq Fan blowing air in the same direction as rear case intake fan
  • Room temp of 72F (22C), air conditioned and constant

Idle = Running for several hours with case closed
Load = 1 hour Orthos, small FFTs, case closed

Chipset temperature, according to Asus PC-Probe and Speedfan 4.32
Idle: 44C
Load: 55C


With Antec VCool @ medium speed mounted as shown in picture below: (blowing air down across the chipset heatpipes).
Idle: 40C
Load: 47C


With VCool and Antec Spot Cool @ medium speed mounted as shown in picture below (actually, it's facing the wrong way in the picture below - I didn't get a picture after I flipped it around)
Idle: 38C
Load: 45C

With VCool and Antec Spot Cool @ high speed mounted as shown in picture below:
Idle: 37C
Load: 45C


p5k_northbridge_cooling_sm.jpg



p5k_northbridge_cooling2_sm.jpg



I'm in the process of re-running these tests at 460MHz FSB / 1.375V and so far, the chipset temps are ~1-2C higher in each scenario.
 
Nice results. If I ended up pushing high FSB I'll try putting the asus add-on fan. I have a spare one from an older asus motherboard.
 
Oh yeah - I bought one of the Asus optional chipset fans today - it actually fits ok but it blocks ~ 40% of the space between the Tuniq and the rear case fan so I decided not to install it.

It would be interesting to see how much of a drop in chipset temps I get... perhaps on a different weekend :)
 
Lol your Tuniq Tower fan assembly is backwards. Was wondering why it looked wierd. Dont think it make much difference though :p
 
lixuelai said:
Lol your Tuniq Tower fan assembly is backwards. Was wondering why it looked wierd. Dont think it make much difference though :p
Click to expand...

For a Lian-Li case, it is "forwards" actually! ;)

(cool air blows in from the back of the case and exhausts out the side and the top/front)

See the nice animation HERE (at the bottom of the page)



edit: Ooooh, the top plate - yeah, when I swapped in the silverstone fan, I attached it backwards - so I just put it in upside-down for now lol
 
i think i'm just gonna try to throw an 80mm case fan on there somewhere to see if it helps, mine sits at 43C idle :S

I'd like to get one of those asus fans but haven't looked to see if i can find 'em yet.

Edit: ok i went and looked for one and noticed all the graphics show that the fan sits over the other sinks not the actual NB itself, does it help much being on there? I don't have room to put it on there as I have a radiator mounted just above it...
 
I just ghetto mounted a 40mm fan to the heatpipe/heatsink mounted on the regulaors 5 am today. Temperature dropped from 49 ideal to 44 ideal. calebb, if you're not using the optional Asus cooler, I'd be happy to buy it from you to return my case to a neat looking state.
 
I don't know about those 2 fans, but using a small 60mm fan on top of my Video Card works wonders for me..

I could even use an 80mm fan there, low speed so it won't move, or controlled with a fan controller to reduce its speed!

BTW, my chipset idles @ 34c - 37c

PC is overclocked @ 3.6ghz with a 400 FSB and 1200mhz RAM 1.4V on the NB!


UNO.jpg


DOS.jpg
 
BillParrish said:
This might interest you guys, forget the gigabyte stuff, its got some great thermal camera pics of the Asus PK5 board showing where the hot spots are (FETs)

( I get a big kick on the Giga board on how the underside heatsink is not even where the most heat is generated "crazy cool" fer sure. :rolleyes: )

http://images.tweaktown.com/imagebank/news_gigaasusttst.pdf
Click to expand...

Cool post! Yeah, those MOSFETS are rated for pretty high temps. I think they use 145C solder and are actually safe to operate right up to that point. It doesn't mention what sorta cooling they did for that experiment either -


And, as far as noise, on medium speed, all the extra fans are significantly quieter (inaudible) than the 120mm case fans ~80%.
 
So with heat on topic, would the asus p5k or the gigabyte p35 be a better overclocker?
 
Metalarm said:
So with heat on topic, would the asus p5k or the gigabyte p35 be a better overclocker?
Click to expand...

Well, the bottom line is, there is no sign that the heat with the Asus causes any problems whatsoever. I guess it's just the 'enthusiast' in all of us here that wants to keep things as cool as possible. So keep in mind, that this Asus motherboard design is "working as intended."

That said, check out this thread. (It's long, so I just linked ya to page 14). Basically, the Asus P5K wins.

As far as overclocking? I think the P5K takes the crown there as well, but I can't find any reviews comparing the two right now.
 
I've got some spare Scythe 120s left over from the build, I should just plop one on top of the video card and aim it at the NB/RAM :)

I could see this as maybe a reason to mount the heatsink north-south, so that it's blowing up towards the top exhaust fans, and then point the rear fan to blow in. That combo would blow on at least the 2 rearmost heatsinks, if not getting any air on the NB. Dunno if I wanna do that though. Maybe after a while, I still haven't gotten the new system into it's regular room yet, and that room runs warmer than where it is at the moment. blah.
 
I have an antec p80 case (i think) and it has a mount and grill on the side panel for an 80mm fan so i just slapped that in and put the side on and i'm now at 39c under load... I have a 120 pulling in and a 120 pushing out and an 80 on the side pulling in now too.

now if i could only get my cpu temps under 60c :eek: (under load at 3.2ghz on my E4300)

i think it's time for a new waterblock... and an updated sig haha
 
Metalarm said:
So with heat on topic, would the asus p5k or the gigabyte p35 be a better overclocker?
Click to expand...

Everything I have read says the Asus. I posted here so the guys could see the pics. That post seemed a liltte too biased for my tastes (and I own a Gigabyte) so while temps mattter, as you can see from this post, the serious OCers here are more than aware and know how to take care of heat issues. Frankly there is not a board made by anyone that I would put in a case without redoing all the chipset cooling. The workmanship of every damn one of them is shamefull and I would not consider anything other than a mild OC without doing the board thermal rework first.

This made me think that (afaik) no review site preps boards properly other than slap an aftermarket HS/fan on, so its the luck of the factory draw on the quality of paste application and hardware for the chipset cooling. So all the OCing information they tout in reviews is not very valid, at least to me. I guess its better than nothing.
 
Call me crazy, but I was looking at my HSF again with it partially sitting over the NB, quite like Orion's pics here, and I'm wondering how much air from the HSF fan may be hitting the NB anyway. Granted it's pushing that air into the heatsink, but some of it also gets pushed up and down when it hits the face of the heatsink, I can feel the air pushing out of the top a bit. I wonder if putting some kind of covering matierial over the gap at the top would force more air down towards the NB? At the very least, maybe more through the heatsink itself.
 
any air flow is better than none for passive NB heatsinks... zalman fan bracket is best for vertical mounted in case systems... or for bench setups you can always do this

nautilus500_mod2.jpg


I used a motherboard tray as the back side components i assume will get hot so best not to have them sandwiched without gaps



:D
 
P35 is nowhere near as hot as 680i mate, also I want to know where's the asus probe temp sensor for the chipset it ain't on my mobo ? is that the mobo temp you read out in probe ? I have no chipset temperature in my bios to be read out...:confused:

????? Chipset temperature, according to Asus PC-Probe and Speedfan 4.32 ?????
Idle: 44C ?????
Load: 55C ?????
 
annaconda said:
Damn so P35 is as hot as 680i chipset. How is your overclocking ?
Click to expand...
nah no way as hot as 680i just it pays in to have it as cool as it can be for overclocking at the extreme end

overclocks fine http://i4memory.com/showthread.php?t=4027 even got my Q6600 to 4009Mhz cpuz validation on water http://i4memory.com/showthread.php?t=4119

@4009Mhz at 1.65v bios set
cpuz validation​

cpuz_validated.png


Wprime 32M @3977Mhz at 1.6375v bios​

Managed to pull off wprime 32M @3977Mhz - took three runs to get it to pass hehe

wprime_32m_11s172ms.png


Everest Bandwidth at those clocks

everest_bandwidth.png
 
I am in love with this board. and its a shame I have to wait to buy it to go with my new build.

But wow @ that Q6600 :)
 
Neat, hadn't looked at one of those zalman mounts before. What's the mount going to get screwed onto though? The screws holding down rear slot brackets? And which of the P5K's heatsinks would be the top choice for cooling? (besides "all of them" :) ). I'll have to compare stock temps to OCed, curious to see the difference now that I've got the case buttoned up.

I was quite chuffed to find that Everest can be set up to give the system readings on my Logi G15 keyboard LCD display, now I don't have to worry about what patches and hacks I need to do to get MBM working on this system.
 
zalman fan bracket screws into the PCI slot holes as a plate on top of your PCI device bracket
 
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