Watercooling loop questions

[asim1999]

Regarding my last thread, companies sponsor people for uni and other career related stuff (like building computers and such) at the school event i am going to, so i will see if they will sponsor me to build a watercooled PC as my rig is having some major issues (GPU and PSU related).

Now, onto the question, if i do get a lot of money, i will be (hopefully) running dual 480 rads in a 900D with 980s for 1 rad and a 5960X for the other one. 

here are my two questions:

1) should i get a tall resevoir/pump combo, a dual 5.25inch bay res and pump combo, or get 2 separate units?

2) if i run both rads in a single loop, how will the heat of one component affect the other (e.g, if i am running the CPU under full load via one rad and the GPUs are idling connected to the other radiator, how much will the idle temps be affected(?

[C0LL0SS0S]

Since the 900D is such a big Case I would get a large Res. If you wanna run everything in loop just try to get sth like CPU RAD PUMP/RES GPU RAD CPU or something so the water is cooled before reaching the other part

[Syntaxvgm]

Most people run them in a common loop, and it will not affect the temperature much. The water loops several times before any major temperature changes are made. 

[asim1999]

Since the 900D is such a big Case I would get a large Res. If you wanna run everything in loop just try to get sth like CPU RAD PUMP/RES GPU RAD CPU or something so the water is cooled before reaching the other part

Thanks, but how much are temps affected?

[asim1999]

Most people run them in a common loop, and it will not affect the temperature much. The water loops several times before any major temperature changes are made. 

Thanks, so i will see no change in idle temps when maxing out an overclocked CPU?

[C0LL0SS0S]

Thanks, but how much are temps affected?

Just guessing about 2-5degrees if you do it right, so nothing to be scared off

[nj4ck]

1) combos can be nice when space is limited. However in the 900D it makes more sense to get the two parts seperately, since you will have much less of a hard time dampening the pump. Bayres-combos are extremely hard to dampen and tend to be loud as hell. 

2) it doesn't matter. Even with your CPU running 100% and your GPU idling, the temperature difference within the loop will be less than 1, maybe 2°C. This is because water has such a high heat capacity, it needs to absorb over 4 Joules of heat for 1 gram of it to increase in temperature by 1°C. That's why it doesn't make sense to build two seperate loops.

[Syntaxvgm]

Thanks, so i will see no change in idle temps when maxing out an overclocked CPU?

Maybe a little. I would look up some build guides on OCN and see what temperatures they report.  A lot of people put a rad between the cpu and the GPUs on the loop, and if you are worried, do that. But personally, it doesn't matter to me much, I have no problem running them in a row. Think about the GPUs: a lot of people run them in parellel, but done run them as a series. And if you are not in game, or not playing a game that supports crossfire/sli well, the first card will heat up and not the others. And it doesn't really seem to be an issue. I've personally never looked at it much aside from the dual cpu build I did. 

Even with all of your rads grouped and the CPU and the GPUs next to each other, I would expect to see no more than 1 or 2c difference. 

[asim1999]

1) combos can be nice when space is limited. However in the 900D it makes more sense to get the two parts seperately, since you will have much less of a hard time dampening the pump. Bayres-combos are extremely hard to dampen and tend to be loud as hell. 

2) it doesn't matter. Even with your CPU running 100% and your GPU idling, the temperature difference within the loop will be less than 1, maybe 2°C. This is because water has such a high heat capacity, it needs to absorb over 4 Joules of heat for 1 gram of it to increase in temperature by 1°C. That's why it doesn't make sense to build two seperate loops.

Oh ok, people in my school who have done watercooling hate dual res bays 

[nj4ck]

Oh ok, people in my school who have done watercooling hate dual res bays 

Many people choose dual bay res combos as a cheap and convenient solution. The problem is that especially the cheap ones tend to leak and have terrible pumps, besides the aforementioned vibrations.

[asim1999]

Many people choose dual bay res combos as a cheap and convenient solution. The problem is that especially the cheap ones tend to leak and have terrible pump, besides the aforementioned vibrations.

But i have seen £150 ones with dual D5 Varios. are they worth it?

[nj4ck]

But i have seen £150 ones with dual D5 Varios. are they worth it?

They won't leak, but you'll still have vibrations. And its a waste of money, nobody needs two D5s.

[Chiobe]

They won't leak, but you'll still have vibrations. And its a waste of money, nobody needs two D5s.

For dual loop, you need both of them.

[nj4ck]

For dual loop, you need both of them.

yeah and nobody needs a dual loop.

[GhostHitWall]

Well there so too many variants.
First, a rad performance correlates to your fan config.  You need to compare to the set-up of people who actually have a 5960X.

For 980s, I have two in a separate loop with a Hardware Labs GTX480 push-pull.  Room temp is always around 20~25c.  With no fans running, very low pump speed(D5 at 2000rpm), their temperature are around 33c the most just doing basic task, web-browsing, youtube, movie that kinda stuff.

I do notice the temp builds up overtime, but very slowly.  From 30c to 33c takes over 6 hours in my case.

 

[Benji_w]

Oh ok, people in my school who have done watercooling hate dual res bays 

 

School? Sponsorship? Wild fantasy build?... Where's my popcorn?

[Benji_w]

yeah and nobody needs a dual loop.

 

Yeah nobody needs anything more than a 212 according to many on this forum... At the end of the day there is no need for custom loops other than better temps and looks, so if I had the choice I'd go dual loop too.

[GhostHitWall]

There is practical use of dual loops or multi D5 pump set-ups.

For dual loop.  Maintenance it is.... when your gpu needs either a swap or replacement.. You gotta believe me that the customer service and RMA process we have in North America is outstanding compare to what I dealt with in Asia.  You don't want the whole system down for too long....
If you have more than one gpu... this benefit starts shining...

Oh and not to mention if you have too many hardline bends and really need pump in series or parallel..
Whether it justify the cost is total opinion since you can't find an identical cheaper alternative.

[nj4ck]

Yeah nobody needs anything more than a 212 according to many on this forum... At the end of the day there is no need for custom loops other than better temps and looks, so if I had the choice I'd go dual loop too.

A custom loop offers a pretty noticable advantage over a 212. A dual loop offers absolutely zero advantages over a single loop. It doesn't give you better temps, it doesn't give you better performance, airflow, anything. All it does is add more noise and vibration with a second pump and cost more. Its just plain stupid.

[asim1999]

A custom loop offers a pretty noticable advantage over a 212. A dual loop offers absolutely zero advantages over a single loop. It doesn't give you better temps, it doesn't give you better performance, airflow, anything. All it does is add more noise and vibration with a second pump and cost more. Its just plain stupid.

And so it adds a second point of failure?

[nj4ck]

And so it adds a second point of failure?

yes, that's another point.