DD 7800 block eta?

[Erasmus354]

water doesnt heat up, adding second fan to my double heater core made sure of that

prescott outputs somwhere around 150 watts of heat not 100 i got a d5 and it appears to move a ton of water, i just assumed the prescott heated up the water a lot but the rad cooled it right back down AND with everything fully loaded i feel the inlet for the rad, its warm compared to ambient, the outlet, its same as ambient temp, after the cpu it gets warm the gpu doesnt seem to do much to the heat its mostly the cpu's doing


also i find it hard to belive that two 80 cfm fans on a rad isnt enough cooling if its not i could add another rad, i sure got a pump powerful enough to handle it, would i get significantly lower temps doing such? that would be a nice thing to hear

Actually the 3.8 outputs 115W, and even at 115W you have a D5 so the water is flowing much faster than 2lpm. Lets say it is going at 3lpm to be conservative and also take your high 150W number.

Water has a specific heat of 4180 joules meaning it takes 4180 joules of energy to heat one litre of water by 1C. 3lpm means that 3 litres move through the waterblock in one minutes. 150W is 150 joules per second, or 9000 joules. So you take 4180*3 = 12540. So in this worst case scenario where you have an abnormally hot prescott, and a moderate flow the temperature differential between the inlet and outlet of the waterblock is only 0.7C. Now if you can tell a difference of 0.7C by feeling the tubing I think you should go apply to work for NASA or something .

Bottom line, water temperature does not vary throughout a loop by very much at all. However when you add more heat to the loop you are raising the amount of heat the radiator needs to dissipate. A radiator dissipates more heat as the delta T increases. So when you add more heat to the loop the equilibrium temperature of the water increases.

More air flow is all fine and dandy, but a larger radiator is much better. If when you added a little bit more heat to the loop the temperatures increased by 6C you know you are pushing the limits of your radiator. Any more questions?

 

[ryuji]

would a 7 degree delta 100% idle vs 100% load be thanks to water temp raising? and i really do feel a diff in water temp going into the rad compared to out, maybe my cpus outputting a crazy ammount of heat? my nephew feels it too

if it would help you out at all, my video card idles at 38~40C and loads at about 46-48C with my room at 80F

my pcs power consumption as a whole is 400 watts if thats any help as well

 

[Light1984]

alrighty.. back on topic now, kinda. this "discussion" brought up another question. i was under the assumption that a gpu+ram would be better than just a gpu solution. so, as a few of you have pointed out, that is not the case. So my question: what would be the best solution for a moderate overclock running a gtx and an A64 3700. im pretty much dead set on a TDX block for the cpu, but as for the gpu, what would be the best, and what ram sinks should i get, or do i just leave the stock ones on?

 

[ryuji]

Depending on what size case, and what radiator you have now, I might even just dump the old radiator (especially if it is only 80mm x2 size), and buy a far better one. The key is sizing your heatload to your heat rejection. Personally, I feel the best place to start is with a quality radiator, rather than throwing a ton of CFM on top of it from the get go. The thermochill line, although expensive, is currently, imo, the best out there. Especially if you need a compact radiator, I would go with the one designed by cathar.

i have a 77' bonneville heatercore or equivalent with two 120 mm antec tricool fans that top out at 80 cfm setup as such, im thinking if i need more rad space i can add one to the top of the case or would this give me little/no returns?

 

[ryuji]

alrighty.. back on topic now, kinda. this "discussion" brought up another question. i was under the assumption that a gpu+ram would be better than just a gpu solution. so, as a few of you have pointed out, that is not the case. So my question: what would be the best solution for a moderate overclock running a gtx and an A64 3700. im pretty much dead set on a TDX block for the cpu, but as for the gpu, what would be the best, and what ram sinks should i get, or do i just leave the stock ones on?

i left my stock ones, sorry for the previous tangent/posts my stock ones with a fan setup(vantec fan card is probably the easiest/best route and would take care of the voltage regulator) my dd maze4 is prob the best out of what you can buy right now, there is a new swiftech coming out soon but i dont see it getting lower then 38C idle

 

[Light1984]

i left my stock ones, sorry for the previous tangent/posts my stock ones with a fan setup(vantec fan card is probably the easiest/best route and would take care of the voltage regulator) my dd maze4 is prob the best out of what you can buy right now, there is a new swiftech coming out soon but i dont see it getting lower then 38C idle

The MCW55 is what you are referring to as far as swiftechs new block?

 

[ryuji]

The MCW55 is what you are referring to as far as swiftechs new block?

yea people have high expectations for them but i dont see water getting much better at cooling graphics cards, so maybe swiftechs got somthing thats only like 2 degs cooler tops maybe? i could be absolutly wrong tho

 

[Light1984]

it seems like is on sale direct from swiftech, but you have to call in i think, anyone know where i can get one?

edit: k, i found them onsale for 50 bucks at performance-pcs.com someone grab one and let us know how it performs