T-bird 800 with Alpha PAL6035 temp too high! Update: It's fixed. 43C at full load.(UT)

[TexasAggie]

I am not happy with the full load temps I am seeing with my new tbird and I hope someone here can help me figure out the problem.
Here's the specs:
Tbird 800 (not overclocked....yet)
Abit KT7 Raid (not yet updated to UL BIOS)
Alpha PAL6035 (Sunon fan sucking away from the core, using Si based thermal grease)
Antec SX830 (Two 80mm case fans blowing out of the back of the case)
Elsa Geforce, Pioneer 104s, Plextor 8/4/32, SB Live Value, Samsung 900NF, etc

Case Temp: 28-29C
Idle Temp: 32-33C
Full Load: 52-53C (Unreal Tournament)

After the original heatsink install I got full load temps of 57-60C. I removed the heatsink and reapplied the paste and it dropped to 52-53C.
I realize these temps aren't dangerous, but I see people on this board lesser hsf's getting better temps with overclocked tbirds. I feel the Alpha should keep it at 45-46C under full load. I have done a keyword search in the forums to see if this question had been answered before, but I didn't find anything helpful. Any suggestions. Thanks.

 

[loogie]

Suggestion...go to a real university.
Those temperatures seem fine to me. My only suggestion would be to try some arctic silver.

 

[clunk]

I have the same CPU/MB/fan except that I keep it O/Ced to 900MHz (1.75V). Under full load (several rounds of UT), I only get up to 47C (and it dissipates very quickly after exiting game). I'm using the generic grease that came with the fan (from 2cooltek). You might check the Alpha and make sure that the bottom is completely flat (use straignt edge) and also make sure that you're only using a thin film of grease.

My 800 will do 950 w 1.85V (almost completely stable ... one lockup while playing a DVD) but the full load temps push 50C. System is plenty fast at 900MHz so I keep it there.

Good Luck.

 

[markymark618]

Flip the fan so that it blows onto the core.

 

[TexasAggie]

Thanks for the help. Does anyone else have other ideas?
Clunk...I am also using the thermal grease from 2cooltek.

 

[Mem]

What markymark618 said is a good idea,I`ve two 80mm Sunon fans blowing,one on to CPU(T-bird 900) & the other over PCI slots this is doing a great job of keeping things cool,if you are not happy get another fan,& experiment with different positions(this is what I did).

 

[EMAN]

I heard socket A processors should use thermal compound instead of grease. Check and make sure the heatsink is alligned with the core of the chip.

Personally I use silver grease and I've got my duron 600@1000mhz

I know overclocking isn't about the cooling but the combination of good core and good cooling.

 

[Eeks]

Shouldnt the heatsink fan be blowing off the cpu? Not onto?

 

[Skiracer]

I am running the same setup except:
800 Tbird OCd to 945 @1.75 Vdc Core
Delta 38 CFM Fan on the PAL6035- Arctic silver compound
Full load- 43 C, 34 C idle (Case temp 27 C)
Your idle temps are fine, but your full load temps are a little higher than mine. This could be due to a couple of things- one, your case fans aren't keeping up with the high heat loads (unlikely since your case temps are fine), or you have a heat transfer problem to the HSF.

My guess is that you may have used TOO much thermal compound! Take your HSF off of the CPU and clean all of the old compound off of the CPU AND the HSF. Use rubbing alcohol on a soft cotton cloth if you have some. Caution- flamable! Just use enough to wet the cloth- don't pour it onto the CPU (I know- this seems obvious, but I have seen it done.) Once the CPU/HSF is clean and dry, apply a THIN coat of thermal compound to the top of the CPU die (only), and a very thin coat to the bottom of the HS where it contacts the die. You may want to use a swab rather than your finger, but I don't think it makes much difference. Then carefully place the HSF assy. down onto the CPU and with GENTLE and even downward pressure, rotate (DO NOT ROCK!)the HSF back and forth a few times to get intimate contact between the HS and the CPU. Then clip the HSF to the Socket and fire the sucker up! If you are still getting temps that seem to high, get some Artic Silver and repeat the process. Another thought- make sure that your CPU Core voltage is set at the default for the tbird (1.75 Vdc, I believe), and check in the BIOS health monitor for actual core voltage (the KT7 is always a little higher than the set point.)

Leave the fan SUCKING on the HS- Alpha knows what they are doing. You can maximize heat transfer by having the coolest air contacting the hottest portion of the heatsink, and at the highest velocity possible. This is achieved by pulling the cool air INTO the lower (hotter) portion of the heatsink. If you blow the air down into the heatsink, the cool air contacts the relatively cooler tops of the heatsink first, warming and slowing the air before it gets to the hottest part of the heatsink. Remember, Q=U*A*Delta T. The bigger the delta T (temperature difference between the cooling fluid and the hot surface), the more heat transfer (Q) you get for a given Area (A) and heat transfer coefficient (U). U can be maximized by making the boundry layer thinner (by increasing the velocity and thus turbulence) of the air. This is why Alpha uses fans that suck, as well as why they use the shroud (to increase velocty and to pull the cool air across the hottest part of the heatsink).

Sorry about the novel, but I have noticed quit a bit of confusion in these forums as to the physics of heat transfer, and hopefully someone else will benefit from this post.

Good luck, and try to get your 800 up to 950- most of the chips will do it very well.

 

[Spankusoverymuch]

Two Fans. One should be blowing, the other should be sucking. Damn, does that sound good or what.

 

[DaddyG]

You should apply the compound using the edge of a razor blade or a credit card. Never use your finger, the grease on your finger will mess up the compound. Wouldn't use a swab either, you need a straight edge like CC or blade.

 

[Hardware]

The alpha 6035 and tb dont mix get another cooler!

 

[John]

<< The alpha 6035 and tb dont mix get another cooler! >>



Huh? That is the best cooling kit available on the market for a socket A cpu.

 

[PochiePooh]

Hardware is joking...I hope.

 

[John]

No smiley and he used an ! so I wasn't sure....LOL.

 

[Danlz]

You might want to check this out: http://www.hardocp.com/reviews/cooling/s37arndup/index.html
HardOCP had to trim the tips of Alpha's plastic feet for good contact! I understand the clips are now revised.

 

[Hardware]

The 6035 wont deliver the 16-24 pound pressure on the cpu!
-> dont use it with a tb/duron

 

[X14]

There must be poor contact between the Alpha and the TB to get those temps. There is now way a properly installed Alpha should be producing 50C at default.

I've got a TB800 @960 1.85V.
Alpha w/ Sunon fan
ambient 78F
idle 86F
full load 109F

Alpha w/ black label Delta fan
ambient 78F
idle 86F
full load 105F

When the A/C is on I get real good temps
ambient 71F
idle 77F
full load 96F

From my results, the ambient temp has a disproportionate effect on cooling. i.e. a 7F decrease in ambient resulted in a 9F decrease in full load temp.

 

[TexasAggie]

Thanks for the help everyone. After reading your suggestions and rereading the hardocp article I decided to try to bend the clip a little so that it put more pressure on the core. I only made things worse. When I booted the machine back up after reinstalling the hsf my new temperatures were:
case: 29C
CPU idle 43-44C
CPU full load >57C
I tore a mirror out of one of my fiance's makeup compacts and tried to see if I could see any space between the core and the bottom of the hsf. I couldn't really tell, but what I did see was that the hsf was leaning. One side was about 1-2 mm higher than the other. If I pushed on the high side of the hsf the temp would go down. I had to go to bed so I wasn't able to try to install it again.

For anyone who has a KT7 and a Alpha 6035...
Which side of the clip do you install first, the one with the moveable flap or the one with the wire loop? Also which side do you put the moveable flap on, the side with all of the capacitors (towards the bottom of the case) or the other side. After I was in bed I started wondering if one side of the clip was longer(see drawing below). I hadn't payed attention before, but does the clip put pressure in the center of the hsf or off center and above the location of the core (the hsf is centered over the socket, but the core is not centered on the socket...I think). Anyways I'd better start working now. Thanks.


____ _________
/ \ / \
/ \__/ | PAL6035 clip..is this what it looks like(dip off center)

 

[X14]

The wire loop end should go by the capacitors and the movable flap end goes out by the power supply side. I'm assuming you have the correct heatsink that does not have pads on it. The only pads should be on the TBird. Hopefully you did not cut off the pads from the TBird.

The pads act as leveler for the HSF before you clamp it down. Since the pads are slightly above the core level the HSF shouldn't be touching the core and should be resting on the 4 pads when you hook on the wire loop end. Make sure once you hook the wire loop on, you straighten the HSF so that the movable flap clip is directly above the knotch on the socket.

You want to be able to hook the movable flap on the knotch all in one motion without moving the HSF side to side. If you don't have small hands and the everything is in the case, this can be quite a difficult task. The Alpha does not have the best designed clip and frankly, it is a real pain to get it on.

Make sure you have your thermal paste applied. This is how I apply my thermal paste and I use just my finger. I don't bother w/ credit cards and razor blades. I just clean my finger w/ alcohol and apply a real thin layer of thermal paste to both the core and the HSF area the contacts the core. I mean real thin. Then I put a tiny bead of thermal paste about the size of a sesame seed in the center of the core. Some people won't agree w/ this method but the 10 lbs. of pressure the clip is supposed to be applying on the core is more than enough pressure to squeeze out that tiny bead of paste.

This method works for me and as you can see in my post above. My temps are about as low as I've seen for TB w/ Alpha setups.

Also, if you noticed, there are only 2 ways you can position the Alpha since the clip will go on the HS in only one direction. The pins on the HS will not all allow you to put the clip on in the other direction. The HS has recessed edges on two adjacent sides kind of like an &quot;L&quot;. Make sure that one of the recessed edges is on the moveable flap side. There is only one way you can do this. If it's on backwards, the recessed edge will be by the capacitors.

 

[troubledshooter]

Sereral things.

1. KT7 Thermistors are notoriously inaccurate. The people who post their temps have VERY little idea what their real temp is (no offense to those of you who know this and factor this in). I have the same setup and spent a whole day bending and rebending my thermistor to get it properly touching my core. In fact, my temp reports are probably about 2-3 C cooler than fact even so. This is just understood. If your goal is overclocking, do it. Find out where you are stable. Screw the temp.

Also, where are those temps from?

Get RC5 to check CPU under load without exiting UT. It will keep CPU usage @ 100% as long as you let it.

best of luck

 

[Whitedog]

CPU Fans should ALWAYS be blowing on the Heatsink, not &quot;sucking&quot; air off of it!

Unless the Fan is drawing air OUTSIDE the case (powersupply's) they should ALWAYS be blowing on the device they are cooling. Period.

 

[Mikewarrior2]

WhiteDog,

Yes.

That is why alpha's are designed and work better in the majority of cases pulling air off heatsinks.

But of course, you know better than alpha, right?


Back to the kt7 Thermistor's. Even with the sucker touchign the backside of the cpu, it is touching idle substrate. With new flip-chip manufactured cpu's, the hottest portion is flipped to the heatsink side(original pentiums/k6-2s and 3s were the opposite).

So not only is the thermistor highly inaccurate, it doesn't even get close to measuring core temp. Rather, it measure's air temp behind the cpu.


Mike

 

[formulav8]

Mine is 54c idle. Been like that for a couple months. No problems here. Quit worrying.

 

[TexasAggie]

Thanks again for all of your help, especially X14. I guess the drawing in my last post didn't work. After I posted last time I looked at the pretty pictures in the hardocp article mentioned in a previous post. The pictures agree with what X14 says about the clip, which is just the opposite of what I was doing. Stupid me, it probably lays it all out in the directions and I skipped it.
I had read that the KT7's thermistor were inaccurate, but people said the temps it reported were too low so that had me worried. This agrees with what Mikewarrior2 said about the thermistor measuring the temp on the opposite side of the heat source.
X14..Thermal Paste the size of a sesame seed! If that is all it needs then I have definitely been over-doing it. That seems awful small, but what do I know. I'll try it out after work. Thanks.