My watercooling temperatures

[curnow]

From everything I've read about watercooling my water cooling system should be giving me temperatures about 8 to 10 degrees celsius above the room temp. It is not. My temp right now is 40 degrees. I suppose I should tell who ever is reading this what exactly my setup is. I have a 1100 liter (that is about 290 US gallons) an hour pump, pushing a mix of de-ionized water and water wetter through a new heater core from a 1990 ford escort (which is about 6"x7"x2" and is being cooled with two 33 CFM 80 mm fans) and into a converted heatsink from a boxed (not oem) amd K6-2 500 (similar to this: http://www.overclockers.com/tips92/ ,and I think there is another article on this site about converted heatsinks). I'd like to post a picture of these, but I have no camera. The CPU being cooled is an athlon T-bird 1200 C on a 133 Mhz FSB and all the settings are default. Although, with a lame coolermaster heatsink fan setup I can overclock it stable to 1466 Mhz with no FSB change, and with my watercooling I can get no further than that anyway..... I'm wondering if it was wasted effort and money. If anyone has any suggestions about why my temps are higher than I expected, or any tips about anything I might need to change I would be appreciative. I'm going to see if I can find a camera and scan some pics of what I have done and maybe post them here... are we allowed to pics up?

[The Overclocker]

yes you can put pics up, the only reasons i can this of for you temp to be so high is because or... air bubles, also use an independant monitor such as mm5

[ButcherUK]

What's the water temp in your setup? If the water is a lot cooler than the cpu then it;s a problem with the block, if not then you should consider more agressive fans on the radiator.

[SteenkyBastage]

hey curnow, welcome to oc forums!

i've noticed a few things about watercooling temps you might wanna take into consideration. the main thing being that the in socket probe that is touching the back of your CPU is horribly unacurate when using watercooling.

those temps taken are almost always real high, because the probe is sending a signal to the computer, which uses a mathmatical calculation to "guesstimate" what the cpu temp actually is.

now when you have a HSF on there, the air circulating around the motherboard actually cools off that probe a bit, which the mobo manufacturer has taken into account for and so the temp gets raised to compensate. but with a waterblock, there is no air circulating down there, but the temp sensor is still being treated the same by BIOS and MBM.

try this, take your old fan from the HSF you replaced, and plug it in and hold it over the waterblock. i'd be willing to put money on your temps dropping quite a bit in MBM.

i've noted that with watercooling that my in socket probe reports several deg C higher than the probe i have touching the side of the core. if you're seeing temps of 40C in MBM, i'd be willing to bet your actual temps are in the mid 30's.

now, as far as the rest of your setup, what i've done is get a 120mm high output fan and use it on my radiator. then i add a radio shack rheostat to it so that i can run it slower (run it a 5w instead of 8w 99.99% of the time). this produces excellent results and is extremely quiet.

when you try to overclock, what happens after you try to go past 1466mhz? do you get lockups, no post, etc? overclocking the FSB would let you have more control of your oc (smaller steps).

my athlon 1.2 wont go past 1481 mhz, at least until i do a voltage mod to it. i'm not sure if you already have, but try upping your voltage to the cpu when you overclock to get higher mhz.

anyhow, hope some of this helped. good luck!

and keep us posted

[classy]

A "converted heatsink". Are you absolutely sure this is not your problem. The rest of your setup sounds good. But that waterblock may be the culprit.

[ButcherUK]

I constructed a converted heatsink waterblock and they work fine :)

[curnow]

Okay :-) you guys reply fast, and thank you all very much.

I checked for air bubbles. My converted heatsink waterblock is clear, and I see no air inside. My pump reservoir is clear, and I see no air inside. My hoses are clear, and no air. My heater core on the other hand... I have no idea if there is air trapped in it, although I have flipped and shaken it up, and it appeared to me that I could get no more air out of it. Also, I am using MBM 5 to check my temps.

I have no idea what the water temp inside the cooling system is. The system is closed up now... should I not have sealed the system? I have no access to the coolant inside unless I break open the seal on the reservoir. As for more aggressive fans on the heater core; I am planning one or two 120mm fans with a flow of 100 CFM each.

Extra praise to rabid bob doles advise. I pointed a case fan towards the cpu... voila, I dropped from 42 Celsius to 36 in about 45 seconds. I've done something similar to your rheostat, I have a model train power supply (3.5"x3"x1.5") that outputs 0-18 volts DC that I have used to vary my fan speeds, I can even run them faster than they should be (I'm not sure how safe this is or how it might effect the life of the fan). As for the overclocking; 1466 Mhz is achieved with my voltage set at 1.85 and after 1466 Mhz I do not post

To be honest I've heard very good things about the performance of a heatsink converted into a water block, but I have some concern that mine may not be up to par. I have only a small amount of headroom above the heatsink fins, and I think this might be impeding the water flow. when I hooked it up and just let water go through it there seemed to be a good amount making it through the heatsink itself, but I'm not sure that the path it takes through the heatsink is optimal. I'm considering buying a waterblock on the internet. Actually, I did attempt to purchase a senfu aluminum waterblock from !inferno technologies http://www.inferno-tech.com/ , but after making the order I never heard from them and never received the product (I ordered here because they have a Canadian site, and me being in Canada made the shipping much cheaper).

Thanks guys, any other suggestions are welcome.

[SteenkyBastage]

hey, good deal with the temps.

note that when i aim a fan at my waterblock the external (touching the side of the core, but not connected to MB) temp readind doesn't change, but MBM does, so your temps are closer to that 36C that you got when fanning it.

and also, it may just be that 1466 is the top end for your processor (or close to that). my 1.2 tops out at 1481 and nothing will let me go over that, only thing i haven't tried is a voltage mod (give it more juice).

just to clear things up. are you FSB overclocking, multiplyer or both? i get a lot better results by bringing my FSB up as far as i can get it (148mhz on my kt7a-raid) and then go as close to the 1481 as i can manage with that fsb. heh, that overclocks the ram, and all pci/ide devices too, tho, so beware if you do.

[curnow]

I've only been playing with the multiplier so far. I've had bad luck with the FSB, I can't get it to run past 138