How much can a waterblock safely weigh?
 

I just finished soldering up my waterblocks tonight - finally! I think they came out reasonably well, however I have a MAJOR concern that really didn't put in an appearance until tonight when I actually got all the peices together.

According to the AMD specs, the max weight for a heat sink is 300 grams, or (very roughly) 10 oz. My waterblock weighs in on the cheapo kitchen scale at between 1.25 and 1.5 pounds, or 20-24 oz. This is more than TWICE the AMD spec. It also does not include the weight of the clip hardware itself, but is just the block.

If I was using a 4-bolt mount, I wouldn't be to terribly worried, but unfortuneately, the mobo I'm going to be using doesn't have the holes for a 4-bolt, so I'm going to have to use a clip on mount. I am planning to do a 6 tab mount, but it will still be a clip on.

How much of a problem is this? I know that the AMD specs were written with the idea that the heatsink would be an HSF with long fins and a fan, which is a fairly long lever arm load on the socket. My WB is much shorter, approx 1" tall, not counting the barbs.

The entire block is copper, the base is 3/4" thick, and about 1/2-2/3 of that was removed to create the water passages. The top is 1/4" thick, and solid except for the barbs. Length is about 80mm and width is about 60mm. If I need to get rid of weight, I probably could mill a considerable amount off the top, since I really don't need to be 1/4" thick except right around the barbs. However I would have a hard time getting rid of weight anywhere else, my passages fill most of the base to the point where I really couldn't shave it very much.

Am I OK, or should I panic??? I spent so much time on these blocks that I don't really want to start over, but I will if I have to....

Gooserider

You have to be the first person I know that's banging his head on the weight wall!

Yeah it's heavy, but many waterblocks exceed the AMD spec.

The clamping pressure can reach 30 lbs, when using a clip mount, and still meet AMD specs, so I'd bet on that.

I think you'll be fine, but if you ever do it again...:p

Thanks for the good news... I'd hate to have to start over at this point!

I might do a quick run around the top to take off an ounce or so because I can, :D but won't make a big deal about it.

I need to make a seat for the clamping spring anyway. I've gotten some 50lb 'die springs' from McMasters, my plan is to make a pair of 3 tab plates for each CPU that will stick up above the block about 1.5", with a piece of 1/2" stainless bar connecting them. Over the center of the CPU die I'll put a 1/4" threaded hole. A bolt or peice of threaded rod goes through the hole almost to the top of the block, but not quite. A nut and washer big enough to go over the end of the spring goes on the rod, followed by the spring. The spring pushes the WB onto the CPU when the nut is tightened down, and pressure can be determined by the amount of spring compression. (McMasters reccomended 15-20% compression, which works out to about 25 pounds)

Sound reasonable?

Gooserider

What motherboard?
 

What motherboard are you going to be using? There are plenty of good AMD boards with the four mounting holes.

Yeah, that sounds good GR.

Tyan Thunder K7X, S2468UGN - Dual AMD, Dual U160, Dual 100mb Ethernet, etc. (Reccomended by Eric S. Raymond, among others...)

About the only downside of the board is that it doesn't have the holes. Tyan created the reference design for dual AMD's, and is reputed to be the most stable and reliable of the type.

Gooserider