i7 Cooling requirements for 3.6GHz OC

[harlam357]

The TRUE has served me well though a bit expensive...

Megahalem. Although any of the ones mentioned are good.

I can't believe it's taken this long for either of these sinks to be mentioned.

I'm using the Megahalems (single ~60cfm fan) on my i7 D0 @3.8GHz and I'm getting into the low 70s under FAH bigadv load.

Installation is a bit of a pain with the Megahalems vs. TRUE - IMO. Performance is about the same I believe... I went with the Megahalems because I didn't own one and already own a TRUE. When I move my i7 setup to a case... depending on any clearance issues, I may move the TRUE over to the i7 and the Megahalems over to a S775 setup.

 

[augie1111]

I have been doing a lot of research on water cooling lately, since I am getting ready to take the dive. The H50 is designed for the average Joe user, who wants to say they are running WC, but doesn't want to maintain a full loop. There are really too many things that can go wrong with it. For one thing, the radiator on it is just a single 120mm, which would be fine for a CPU only loop, but you can get much better performance and reliability by building your own loop. If my pump fails, I can replace the pump, if the pump fails on the H50, it is garbage. If I spring a leak in my tubing, I can replace the tube, but with the H50 being a completely sealed system, if a tube starts leaking, it can't be replaced.

Those are the biggest drawbacks that I can think of, but I wouldn't trust my rig folding 24/7 with it. You are much better off spending less money on a decent air cooler, as there is much less that can go wrong with one. If you are thinking about going water, in any way, I would recommend doing some research first.

Some excellent points there that I hadn't considered. I know the fluid is called water but is it really water? One would think that using a non-harmful fluid would be a better choice.

 

[augie1111]

I can't believe it's taken this long for either of these sinks to be mentioned.

I'm using the Megahalems (single ~60cfm fan) on my i7 D0 @3.8GHz and I'm getting into the low 70s under FAH bigadv load.

Installation is a bit of a pain with the Megahalems vs. TRUE - IMO. Performance is about the same I believe... I went with the Megahalems because I didn't own one and already own a TRUE. When I move my i7 setup to a case... depending on any clearance issues, I may move the TRUE over to the i7 and the Megahalems over to a S775 setup.

OK, this is more up my alley, low 70's is a bit high but not too bad either. I'll be checking out the measurements as I already have the case, a CM690.

 

[ozzlo]

Speaking of just in case... I have 2 fans on my true just in case one of em dies... Can't have the system throttling way back... I need those bonus points!!!

I got an i7 dud so I really have to push the voltage up just to hit 3.8... Also the temp sensors in this thing are a bit whacky (20c range over 4 sensors) If I average em out, i get about 77c

to get from 3.8 to 3.86 requires I bump up the voltage to the point the chip runs in the high 80's to low 90's

3.92 which is the highest this chip has been stable, I was running @97c I decided against running that 24/7...

of course that is real temp telling me that... SiSoftSandra never puts me over 60c

 

[deadlysyn]

Some excellent points there that I hadn't considered. I know the fluid is called water but is it really water? One would think that using a non-harmful fluid would be a better choice.

If by non-harmful, you mean non-conductive, you are thinking along the right lines. Straight distilled water, with no additives is not conductive, but when running through a water loop, it picks up ions from your radiator, water blocks, and barbs. These ions also cause galvanic corrosion, if you mix metals, like aluminum and copper. Also, certain additives can make it conductive as well.

Because of these issues that can arise, a lot of people have moved to using .999 pure silver in their loops as a biocide. Silver does not react with copper the same way that aluminum will, so you wouldn't have problems with galvanic corrosion. As soon as I get back to my rig, I will see if I can post up a guide for you.

As far as the liquid in the H50, it is most likely distilled water with a biocide or antifreeze. It's real competition is is mid to high end air coolers, but I think a lapped and washer modded TRUE or a stock Megahalems beats it out with push/pull on either one.

 

[augie1111]

If by non-harmful, you mean non-conductive, you are thinking along the right lines. Straight distilled water, with no additives is not conductive, but when running through a water loop, it picks up ions from your radiator, water blocks, and barbs. These ions also cause galvanic corrosion, if you mix metals, like aluminum and copper. Also, certain additives can make it conductive as well.

Because of these issues that can arise, a lot of people have moved to using .999 pure silver in their loops as a biocide. Silver does not react with copper the same way that aluminum will, so you wouldn't have problems with galvanic corrosion. As soon as I get back to my rig, I will see if I can post up a guide for you.

As far as the liquid in the H50, it is most likely distilled water with a biocide or antifreeze. It's real competition is is mid to high end air coolers, but I think a lapped and washer modded TRUE or a stock Megahalems beats it out with push/pull on either one.

Hehehe, I must have done my homework properly as I understood most of your post. Only thing I haven't heard of is 'washer modded TRUE'. The less work I have to do the better but I'm not averse to trying something that's tried and true either like lapping the heatsink.

The how-to I found went from 400 grit to 2000 in six steps and I could easily do that with a cold beverage at the side. Thanks for the input for this OC'ng n00b as I was afraid of getting too much info if I posted where this thread should have been. I'll post in the appropriate forum for timings/voltages etc. when I get it next month.

Thanks to all who responded. I didn't think that I'd get this much response either. Ya'll are great and the round's on me!

 

[harlam357]

Only thing I haven't heard of is 'washer modded TRUE'.

The how-to I found went from 400 grit to 2000 in six steps and I could easily do that with a cold beverage at the side.

The washer mod is basically just taking an extra washer of appropriate size and placing it in between the "clip" and the heat sink base. This yields more pressure on the mating surface (cpu heat-spreader and the bottom side of the heat sink base) allowing for a tighter fit.

Watch out for those nickel plated bases. I lapped a Thermalright nickel plated base once (SI-97 I do believe) and it took a loooooooonnnnnnggggggg time... of course, I lapped mine all the way down to the copper. You may want to up that beverage allotment to at least a six'er.

Not discouraging you one bit... I think learning to lap is like a right of passage for overclockers. So if you've never lapped before, I suggest you get some old piece of junk heatsink and try it on that first - just to get the feel for it. I've done several heatsinks in my day, but not recetly... I'm just not as overly obsessed with that last 1-2C or that last 100MHz as I used to be.

 

[augie1111]

I'm just not as overly obsessed with that last 1-2C or that last 100MHz as I used to be.

Hmm, OK then. I was under the impression that lapping could give one a 5C reduction in heat which would be nice as I want my hardware to last for a long while. I am not obsessed either with the uber squeeze either, I just want a good and stable machine, heck man I haven't even OC'd my quad yet as 3.4K PPD is just fine with me and I can't expect too much more either.

Now, continuing my philosophy of not making incremental jumps in procs, e.g. from a single to a dual to a quad and not MHz or small gains types of upgrades, that's why I'm looking at the i7. Besides, the mobo I'm looking at has 3 PCI-E slots for my current GPU's.

I would really like to get the bonus points with the i7 and this OC'ing thing is the ticket IMO. Mind you this is almost totally new to me. I wouldn't try this on my own with a $350 CDN chip.

 

[harlam357]

Hmm, OK then. I was under the impression that lapping could give one a 5C reduction in heat which would be nice as I want my hardware to last for a long while.

It may... and I stress may... give you 5C better temps. In my experience, and I'm a marginal lapper at best, I've gotten another 1~2C out of it... ymmv.

It all depends on the lapper and how flat the surface was to begin with. In fact, perfectly flat is not always the best.

The boys from Prolimatech advise against lapping their sinks... http://www.prolimatech.com/

Lapping Warning!
Prolimatech does not condone any type of lapping done to the CPU or to heatsink base. Every Prolimatech's heatsink base is designed on a pin-point scale of how the base is to be flat and/or curved where it's needed to be. We have programed our machines to machine the surface in a very calculated way. Any after-manufacture lapping or modding done to the base will alter the design, hence negating its performance factor as well as its warranty.