Not happy with my W/C temps

[Kevin]

Originally posted by schoolie
OK, my magdrive 3 easily doubled my water flow. It's probably around 90gph. My CPU temp dropped about 1C.

Flowrate most likely isn't your issue. Flow is highly overrated and there have been absolutely zero formal tests showing a lot of flow rates vs. CPU temperatures... but it is good that your temperature has improved. Maybe you've found a flowrate sweet spot. Imagine a curve like y=-(x^2). let x = flowrate and y = efficiency. There is a sweet spot at the top of the curve. Once you push flow too hard, efficiency drops off. Same as if you don't push enough. It looks like you've gotten a bit closer to the sweet spot.

Originally posted by schoolie
I do have one more question. Isn't it true that it doesn't make any difference how thick one applies thermal grease? If the block is properly seated, then the excess AS will squirt out the sides. Comments?

First, think of the theory behind heat transfer. The best possible heat transfer you could have would be to have absolutely zero thermal paste and two theoretically, perfectly, mathematically flat surfaces right on top of eachother. however, we know that there are microflaws within the surface of metals, regardless of how smooth we try to make them. Thermal paste is just designed to fill in the inefficiencies. If you put a lot of thermal paste on, you run a few risks. The first is the possibility of air bubbles getting trapped. As you compress the block down, air can get caught in between all the paste and mar your thermal transfer slightly (granted... these are SMALL pockets of air). Second of all, once again, if ALL the excess paste came out that would be great, but in reality, some will hang under there and cause a VERY slightly non flat bond between the CPU and waterblock. So that's why too much is bad. Follow the instructions on the AS site for best results.

Originally posted by schoolie
Thanks Brad. Why are some people getting 10C over ambient with Vcore=2.05V?

Because the temp readings you are getting on a non-intel board are currently WRONG. You need to wire a thermal diode circuit or wait for the new mobos to get a temp reading. Your temp could be like 3 - 10 degrees off for all you know. For all you know, your CPU temps are much better than you think.

[futRtrubL]

Also some boards have a minimum temp they are allowed to read, since you can't get less than x with a hsf then why would someone need to read temps less than x? ;']
I saw on the web somewhere that someone pelted a socket thermistor (got frost forming on it) and it still reaad 31C.

Edward

[TigerOats]

Originally posted by schoolie
Hate to beat a dead horse, but still no joy. I've lapped my block to 600 grit, increased my flow rate to 90gph, reseated with a lot of ASIII, reseated with a thin film of ASIII. However my core temp is 31C @load, 26C idle, and my ambient temp is 17C and my res temp is 17C. I'm running an AXP 2000+ at 1.921GHZ, with Vcore=2.08V. Is it possible that this sucker is just throwing off a lot of heat? It gets unstable at 35C, and I mean 35C measured by my KR7A thermistor. I have my MAZE2 tightened way down, and the CPU leaves a perfect imprint on the bottom. Arrrgh! What the heck am I doing wrong? Frustrating part is I'm getting worse temps now! Thanks for letting me vent

--Rob

based on your original post ambient=12 load=27 So the delta has decreased by 1C. Are you using the following flow res - pump - radiator - cpu - res?
Also recommend lapping with 1000+ grit and polishing with toothpaste. I don't know if you are going to improve on this with the kind of vcore you are using.

[jaydee]

Originally posted by schoolie
Thanks Brad. Why are some people getting 10C over ambient with Vcore=2.05V? I wish I could go TEC, but electricity is too expensive here

BTW, I tried the Dtek sidewinder, this weekend. I far as I could tell, the performance was comparable to the MAZE2. I also tried the Z4 with 1/2" fittings, but that was not a good experience. My temps were about 3-4C higher with the Z4. Who knows, maybe I did something wrong. I'm sending the Z4 to Jaydee so he can test it.

Most people like myself that are getting 10C over water temp do not have the the XP2000+@1921gigs!!! Be very happy with that temp, at those setting, with that CPU!!! That is a good OC aswell.

If I get that Z4 by Friday I will have my results up by Sunday. I am going out of town Monday the 18th for a bout 5-7 days so I will ship it back to you when I get back unless I have it and am through with it by Saturday.

[pHaestus]

You have to remember that some motherboard sensors won't touch the CPU core at all. Those look like good temps to me, but again it is unknown what the actual temp is. As far as flow rates with the Maze2, I find that anything over 1.1 GPM flow rate doesn't improve performance.

[schoolie]

Thanks for the very rational responses to my emotional outburst I just hate to give up my overclock when warmer weather arrives. I think this CPU is just dumping too many Watts at this voltage and freq. When I removed all of the case ventilation, my true Tcore is closer to 35C at 17C ambient. This would be about 0.163 C/W. The Thermistor is touching the back of the CPU...but it's not the internal diode. pHaestus, I'm waiting for the "Connecting the Thermal Diode to SMBus for Idiots" book to be published

Just seems a shame that I can't have my 5C delta It's nice to benefit from all the experience on this board!

--Rob

[Brad]

I always knew the Z4 sucked