Custom GPU Waterblock

[yngndrw]

Okay, I know there are already threads about this but they are all geared towards CPUs so I thought I'd make a new one.

To cut a long story short, I bought a 226Watt TEC and a Maze4-1 CPU coldplate, and need a waterblock to go with it.

I think I will also get a new coldplate made up as the Maze4-1 CPU coldplate is a bit smaller than I'd like.

Basically, what design should I go for for the waterblock part ? It needs to cool a 50x50 TEC while having the G1/4" barbs on the edge. It will probably be all copper.

I was thinking an apogee (sp?) style base with a Maze4 GPU style cover, however the water around the edges wont flow too well.

Ideas ?

Cheers. :toast:

[ReD.SkY]

how about a MP-1 style ?

u doing this with a CNC ?

[yngndrw]

Not a CNC, just a machinest with a milling machine. I guess he can do everything that a CNC could, but a lot slower. So a simpler design would be a lot better for me.

As for the MP-1 style, it would need to be mighty wide to cool a 50x50mm surface area no ?
http://www.cooltechnica.com/images/AquaXtreme/MP-1/MP-1_exploded_530w.jpg

I'm limited in overall size becuase of:
A) Weight - Think of the 4 tiny screws that hold nVidia coolers on. They aren't too strong. :(
B) Video memory.

[yngndrw]

Right I just looked at some Wintsch Labs blocks and the only internal pic that I could find was this: http://reviews.pimprig.com/cooling/image.php?url=wltec-hotplate.jpg

However, I did notice this, the Wintsch Labs Spider: http://www.pcextreme.com/images/ex-blc-161_1.jpg

It cools either a 50x50mm or 60x60mm (Guestimated by the power rating) TEC, but is not much bigger than the TEC it's self. Does any body have an internal pic of their GPU TEC blocks ?

Anyhow, I was thinking of this as the design. (Attached) What do you think ?
[Blue = barbs, Red = pins / copper]

I know it's simple, but it allows me to keep the block low (Just the height of the barbs) and small. (Slightly larger than a TEC + a bit on one side for the barbs) My concerns with this design are:
A) The divider in the middle covers the part of the TEC which cools the core. All pins / internals will be quite thin, but I'm not sure what effect it will have.
B) I'm not sure what this design will perform like in this application. It needs to be low restriction as I'll be running a Storm in the same loop, but also needs to be able to remove heat from a 226Watt TEC (320Watt electrical power) as well as the 7800GTX it's sitting on / crushing.

Comments ? Crits ? Ideas ?

[XS Janus]

if it was a CPU block I would go for a 2inlet/2outlet designs, I saw a picture on here once if anybody has it....
But that one was not practical on gpu
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[yngndrw]

http://www.frozencpu.com/images/products/detail_hires/ex-blc-134.jpg
That ? Yes it was able to remove massive heatloads, but indeed it is impractical for a GPU.

Any comments on my design ?

[Scarlet Infidel]

I know you haver a cold plate already, but has anyone round here gone for direct peltier cooling? Or does this cause expansion/contraction issues?

[yngndrw]

The problem is that you would only get a small contact area with the TEC, which would effectivly waste most of the cooling effect of the TEC.

AFAIK.

[yngndrw]

Comments / suggestions ???

Note: All of the 'pins' are SLIGHTLY lower than the top of the blocks, to allow the top surface area of the pins to touch the water.

[Plywood99]

Instead of lowering pins, shorten the dividing fin to 2/3 of internal width. Also ditch the half pins connected to dividing fin, very difficult to machine. More important for cooling your tec would be base thickness. I would leave a minimum of 3mm solid copper...

[Jochenp]

It's important with TEC's not do circulate the hot water, but rather "splash" the water in the middle like with an MCW6002

[yngndrw]

Thanks for your replys. They also give some dimensions which are always a benefit. :)

Plywood99: So you're saying that allowing the water to flash over the pins slightly wouldn't have any useful effect ? Okay then thanks for the heads up and the dimensions.

Jochenp: So you're saying that the main place to cool on a TEC is the part that covers the core ? The problem with doing that is the placement of the barbs. I could have a hi-flow design to get the cold water to the center quickly by having three barbs (1 inlet in the middle and two outlets on the outsides.) but I can't fit 3x 1/2" barbs in that space. The only other way of getting water to the center that I can see is to have the inlet in the top, but due to it being a GPU block I can't really do that without adding either a lot of extra height / weight, or by having a flow-killing 90degree rightangle.

Any ideas on how I can adapt the MCW6002 design for a GPU without encountering these problems ?

[Bloody_Sorcerer]

yes; take an MCW6002 (flat base), mod the barbs to a right angle, mod a mounting plate to whatever GPU holes you need, slap a pelt between that and a coldplate, crank it down tight (using the mounting plate and the coldplate) and then bolt it onto your GPU :)

[yngndrw]

Okay the three issues that I can see with that are:
1) Where can I get a flatbase MCW6002 in the UK ? (Or somewhere which will ship to the UK.) I havn't seen them in ages.
2) Right-angle-barbs. I will be running a loop of: DCC+ Ultra, PA120.3, Storm, Maze4 chipset block, and this GPU block. Would the right angle barbs kill the flow rate ? I guess I could mount the output to a non-right angle, but the inlet would be a right angle.
3) Mountings. I was going to just tap some holes into the base and screw the cold plate to that, but how big is the base ? (All dimensions, it needs to be deep enough to get a tightness on the bolts while also being large enough to cover the surface area of the TEC AND where the bolts are.)

Would it be easier / cheaper to get my own copy of the MCW6002 made up with the inlets and mountings that I require ?

Cheers.

[Jochenp]

The reason the design of the mcw6002 is better for tecs is that the water isn't transported over the pins, since tecs put out so much heat, with a design like the maze4 os any channeling desing ,the water is already hot when it's in the middle of the block.
With a 6002 design, water is splashed in the middle and goes away in the sides, only having to travel half the distance.
2 outlets would be perfect though...

[yngndrw]

Well, how about a 6002 with this kind of channeling on top. (Attached pic.)

All the channels would be 1/2" bore.

C&C ?

[Plywood99]

Do not modd a 6002 for dual outlets. It will decrease performance a good amount. I can show internal pics of this block if need be...

[yngndrw]

Are the insides like a giant Apogee base ? Do you think it would be better to get a purpose made one or just mod a 6002 ? Also do you know where I can buy one from and how thick the base is ? Oh and does the block come apart or not ? I don't think it does but just wanna make sure - If it does then it will be easier to machine / mod.

[Plywood99]

Block is soldered together but does come apart. ;)

It would probably suit you best to modd the 6002, don't know where to by them though, I'm in the states.

IIRC base not including pins is 3mm - 4mm thick, perfect for cooling a large die area such as a tec. You could solder a couple of 90 degree elbows onto it and be in business...

[yngndrw]

Do you think the base is thick enough to have holes tapped into it to screw the cold plate to ? I might pull one apart and have a new top made up.

What are the dimensions ?

Also you don't know where to get one over here, but do you know anywhere to get one over in the states who would ship one over here ? I don't mind paying shipping over the water if it's just a small item.

Cheers.

[Plywood99]

Here yah go...

http://www.subzeropcs.com/water_blocks_cpu_vga.html

[yngndrw]

Cheers.

Is it the P4 one which has a flat base ?

[Plywood99]

A64 verson has flat base, so does the p4 version listed since it is for socket 478...

[yngndrw]

Right okay then, might order one tomorrow when it's daytime. :) Cheers for that.

[yngndrw]

Right before I order one, I think I should work out exactly what I'm going to do with it.

Options for changing the barbs are:
*Braze right angle barbs on.
*Make a copper block to braze on top of the whole waterblock, which has two G1/4" threads in for barbs.
*Cut the existing top off and remake it.

Also, for mounting the coldplate I could:
*Braze little copper blocks to the edges, and tap them.
*Tap holes into the base, but having 2-3mm of thread doesn't seem like a good option.
*Make a long coldplate and use a standard mounting to bolt to the cold plate, but this would be harder to insulate and probably wouldn't fit on my graphics card due to the memory anyway.

I've also noticed that the barbs on the 6002 are quite thick walled. Should I re-bore them to make a larger ID ?

Any ideas ?

[Jochenp]

It won't hurt performance :)
When you're at it modding anyway, why not?
I dit it whith my a64 6002 when it arrived...

[yngndrw]

Alright I'll do that then.

Any ideas on which options I should go for ?

[Jochenp]

? options

[yngndrw]

Options for changing the barbs are:
*Braze right angle barbs on.
*Make a copper block to braze on top of the whole waterblock, which has two G1/4" threads in for barbs.
*Cut the existing top off and remake it.

Also, for mounting the coldplate I could:
*Braze little copper blocks to the edges, and tap them.
*Tap holes into the base, but having 2-3mm of thread doesn't seem like a good option.
*Make a long coldplate and use a standard mounting to bolt to the cold plate, but this would be harder to insulate and probably wouldn't fit on my graphics card due to the memory anyway.
Them options.

[Jochenp]

I would braze 2* 45° barbs on, so that the restriction is less.

[yngndrw]

Hmm, that would work mighty well !! Thank you. :)

Edit: How about the mounting though ? Any ideas on that ?

[Jochenp]

Not really, just use what seems like the easiest option and make sure that you can put a LOT of stress to the TEC without stressing the videocard.
More pressure = better performance out of TEC's (and not by 0.1°c, by a LOT (I've heard :p:))

[majestik]

Would be quite difficult to tap the 6002. Maybe use epoxy instead?

[n00b 0f l337]

Not hard to tap the 6002, harder to braze on barbs.

[yngndrw]

How deeply can I safely tap the base then ? I don't want to go right through, or make it too week.

[THE JEW (RaVeN)]

How deeply can I safely tap the base then ? I don't want to go right through, or make it too week.

I *think* the base is around 0.2" thick. So 0.1" - 0.15" is about the max I'd go.

[Burn]

Do you have access to a rotary table?

[yngndrw]

I don't even know what one is, but I would be getting a machinest to do the work anyway.

This project is currently on hold while I finish the basic watercooling in my new case, along with getting a paintball gun. So many project so little money. :P

[Burn]

I hear ya about the money :D

A rotary table basically allows you to rotate a part, you can do it either mounted flat or on a 90 deg. adapter to rotate a part while you mill.

[yngndrw]

I'm not exactly sure what he's got, but he has got one of them manual milling machines with the sliding vice. I'll see what he can do when I get some more money sorted.

Cheers.

[Burn]

A cross-slide vise (What you're talking about) is a ho-hum for doing blocks...They tend to have a ton of backlash and aren't too accurate. Unless he built his own, most store-bought ones aren't acceptable for waterblock making.

[yngndrw]

Well it isn't an extra bought one, it's the one that came with the milling machine. I dunno I'll have to ask him about it when I get it done.

[Scarlet Infidel]

MCW-6002s here. (http://www.overclock.co.uk/home.php?cat=437)

Also, before when i said about direct peltier i made a mistake, i meant that the water hits the peltier directly, there would still be a coldplate on the other side.

Of course you could still use pins for the surface area. But would this give any performance benefit over a thin base of copper theoretically? This is where id imagine expansion issues might come in too.

[yngndrw]

Cheers.

I think with direct TEC cooling, you would get hot-spots on the hot side which could damage it. Also I think it would be quite hard to get decent clamping pressure.

[Scarlet Infidel]

Yeah, thinking about it further i cant see any real advantage.

[Jochenp]

Any development?

[yngndrw]

Any development?
Nope, I'm out of money. :p: Once I get my paintballing stuff I'll get onto making this block.