Extra GPU question

[Supa Koopa]

I'm currently running an Alphacool 360x45 and 280x45 with my I5 4670k at 4.5 and 780ti at 1160. Everything is running well with the gpu never getting past 40c and the cpu around 60c, whether benching or playing. (Unless it's prime 95 or something stupid then I can get the cpu in to the 70's)

I've just bought another 780ti and water block to fit in to it and I'm wondering what's a safe temp for the water. I know the second 780ti is going to pump a lot of heat in to the system and I can't see anywhere to add another rad. After gaming or benching the water get's to around 35c, so how much higher can it go before I have concerns and need to find more rad space. I've got a corsair 750d and if I hadn't have just bought it a month or so ago it I'd get a Primo, but that's out. I can't add another rad to the floor as I use one of the hard drive caddies. Not keen on an external one so not sure what the options are.

My fans are nice around 800rpm but I don't want to go any higher than 1,000 as it starts to get too noisy.

It's getting fitted this weekend so I know it's a case of suck it and see, but I thought I check with more knowledgeable ones.

 

[Uncle Petey]

You shouldn't have any issues there. Your rad space is ideal for a dual card setup.

 

[Disco_P]

Just out of curiosity what are people's personal limits regarding water temps? I've personally chosen 40 but have no reason for it.

 

[Supa Koopa]

Thanks Petey, that's helped as I was a little worried.

I'm the same disco. I keep hearing about this 10c delta t being ideal but it could take a lot of rads to get there. Like I said my water is around 35 but can go up a couple of degrees if the wife's got the heating on too high. I thought a second card could add at least another 5 to 10 degrees which would put me in the 40's. Is this still safe? The tubing is quite flexible at 35.