Mach 2 GT Rebuild Worthwhile?

[-Rogue5-]

Alright, so I rediscovered my old Mach 2 GT a couple of days ago and want to slap it on my i7 920 D0. Before I go wasting time building a 1366 mount (it's got a really sweet S470 kit on there now), I went online to see if the ol' stock GT could even handle the 130w of a i7 920 running stock. While the mach 2 documentation says that it can hold -50c evap temp at 100w load and -20c at 200w load, everyone online says that it can't come close to that without massive help (e.g. new evap, new condenser, new refrigerant.)

SOOOoooo, I log into XS after a slight 7 year hiatus and was hoping to find a quick/easy solution. Turns out I may have been wishful thinking.

Now my questions revolve around whether or not it's worth salvaging. I don't want to spend more than $100, but I also don't need to be ultra cold either. My hope is to have 24/7 operation locked down at -5 to -10c under full load in the 5 or 6GHz territory with the current/upcoming crop of i7s (as in, a 6 or 8 core, 130w SandyBridge-E that I plan to upgrade to next year). THE crux is that I'd like this cooling unit to fit in the Mach 2 GT chassis... I want it to be a consistently performing, self-contained unit and not just a test-bench...

From what I can tell, swapping out the condenser should offer the most benefit in holding down high-loaded temps. If so, does anyone have any recommendations for a bigger-than-stock condenser that would fit in the Mach 2 chassis (with slight modding/cutting, of course)? What if I just used two push-pull fans on the stock condenser? Would that increase efficiency enough to keep my current i7 920 below zero (without frying the compressor)?

Am I going about this all wrong? Should I just abort before getting in too deep? It feels like such a waste having that perfectly performing Mach 2 GT just sitting there. Are there any low-wattage i7s in 1366 that overclock as well as the 920 or 2x00Ks? That might be cheaper and it would allow me to use the stock Mach 2 GT to maintain sub-zero.

[n00b 0f l337]

For the most part it's not possible to do cheaply. $100 won't get you close sadly. And condensers are a bit hard to come by. I have some cubes, but between the condenser, a fan, and a shroud, they run almost to the edge of your price range, and you aren't accounting for refrigerant and time and such. I'd suggest ebaying off the unit.

[Dumo]

Mach II GT stock here with FX8150 8C/8T up to 1.6Vcore benched @ 5.6Ghz.

Dunno about I7 920 though, but 2600K will run @ maximum Mhz with HT off easy

[-Rogue5-]

Thanks for the replies guys; I should probably elaborate. I didn't want to have to spend more than $100 (truthfully, I didn't want to have to spend anything), but it seems I'll have to open the wallet to get it up to snuff.

I also want to have HT enabled. I'll be using this as my video renderer, and most of the applications scale pretty well with multiproc/thread and even with HT helps substantially.

Dumo, I'd be very interested to know what kind of temps are you pulling? The FX8150 is ~125w (only 5w more than the i7's ~130w) at stock.

Also, would cooling the condenser with watercooling or something make the entire system perform better? If I can avoid having to recharge the system, I'd prefer it. I'll be reading Gray's "High Load Vapo/Mach Mod" thread later today to get some ideas. I actually have a second Mach2 with a hole in the condenser somewhere, so I may focus my efforts on chopshopping that one up. I think the hardest part for me to acquire would be a compressor; so will the stock Mach2 compressor (Danfoss something or other) perform well, or is that a pretty weak link in the chain?

EDIT: So I just dug up the non-working, non-GT unit and it has a Danfos 5933 (105G) which had R134a in it. If I can find my radiators, it may be easier to just build a system with the 5933 as the base. Will it be able to handle something better (r404a?) Also, will HVAC guys have a problem recharging the system with another refrigerant (it clearly says r134a right on the side) or do most even give a crap?

I also found a couple of access valves, but still no condensers... I had two that I think would be perfect... both from AC units, so I know they can dissipate the heat. The non-working Mach2 is probably empty (it had a leak when I originally got it and I was planning on fixing it before the GT was acquired.) Should I expect problems with the compressor for having sat empty for a few years? I'm gonna source out a few evaps, but I have a milling machine and some copper, so I may make my own (any good designs out there I should look at?)

[Dumo]

Dumo, I'd be very interested to know what kind of temps are you pulling? The FX8150 is ~125w (only 5w more than the i7's ~130w) at stock.

Heres with 2600K Rougue....I use Duniek's multi socket converter (its easy to make), just don't forget to use heater pad on bottom socket holder for extended usage. Its not adviseable to run it 24/7 without constatnt load on cpu because condensation tend to form when cpu is in idle...








Heres with FX 8150....I only use phase solely for benching. Evaporator temp. around 5C load 8 cores. As long as no reboot then I'm ok with this old Mach II GT..

[-Rogue5-]

Awesome Dumo, thanks!

I was thinking I could just insulate really well and not have to worry about condensation as the cold parts wouldn't be hit by open air. Conversely, I figured the heater pad would only make the evap not get as cold, being that I'm riding so close to overload already. So that heater is still a requirement, huh?

I'm kind of concerned with that constant operation might be the hardest thing to accomplish, now; if I mod my Mach 2 and it doesn't end up working with the Mach 2 controller (for booting, shut-down, and failure alert) I'd basically be back to benching territory, rather than stable operation. Not good.

I also seem to recall a trick for getting an extra 10c cooler by tilting the Mach 2... Does that trick still work or was it for another Off-the-Shelf phase change system?

I'm now looking for TWO old Mach 2/GT/VapoChill Condensers, but can't find anything for sale anywhere? I'm thinking of rocking dually-condensers rather than one large one, and trying to cram it back into the Mach2 chassis... I just need to find an oxyace torch, .031 or .042 captube, a dryer, a new evap, and someone to vac and recharge with r404, and I'll be set.

EDIT: I just found this:
http://ocxtreme.org/forumenus/showthread.php?t=2002
Is duniek soldering together the GPU evap on a stove? There's no way it gets to proper brazing temp.