{multithumb} 8800GTS and VID-280
I've been cooling my cpu with my Exos II for I guess two years now, five more years with other systems. In that time I've fairly done in my share of parts. Given the reservations non water cooling Overclockers have expressed in the forums; I'd just like to say that in all that time I've NEVER lost a part to water leaks. I've never had a water leak. But I've spilled my share of water and coolant! Guess what? It dries out! The components stretch, and they yawn, and they start right up no worse for the wear!
Now I'm not saying you can't kill a computer with water and coolant, you can. I'm saying you have to be careless or less lucky than I have been. But, the danger is real? Yes. But, the benefits are equally compelling. So much so, that I thought I'd start by giving the reader one or two simple facts that water cooling overclockers find very compelling indeed.
I borrowed this snip from the Koolance site:
"Of liquids, water (after mercury) conducts heat the fastest. Its thermal conductivity is about 30 times greater than that of air. And not only that, it holds a lot more heat; it takes over 4 times as much heat to raise the temperature of water as it does air."
What this means is that water has a much greater "heat reservoir". If I may use a non scientific term. Water stores more heat energy, relative to temperature increases when compared to air. This has real implications when trying to cool parts in an environment in which the ambient temperature (room temp) is highly variable. On air, as I'm sure our overclockers have noticed there is a direct and immediate one-to-one temperature relationship to ambient air after the cooler's limit is reached. While water is not immune to the raise of ambient temps, it warms-up far more slowly and continues to conduct heat far more efficiently as the temperatures rise. This creates a far wider response time when adjusting to a higher ambient summertime temperatures. Thus, it is far safer to go faster, skirting the limits of the hardware's temperature tolerance on water than on air. The heat differential between air and the thing to be cooled, must be much greater than it does with water. In other words water will cool a thing of very similar temperatures to it's own temperature. Whereas, air either needs to be much cooler than the part to be cooled, or must pass over the part at a high rate of flow.
While I've been water cooling CPU's for some time now, this is just my second venture into using my Exos II to cool a video card. I started cooling cards with my 7950 GT O/C, and was very pleased with the results. But, there is a dark side to water cooling cards. They are very restricted as to which water jacket can be fitted to and work with which card. Usually, no more than three or four cards can use any given water jacket. The VID-280, supports only one, the 8800 GTS, and it does support SLI.
This is not an arbitrary means of gathering our cash unto the creators of these jackets, whenever we buy a new card! But, it does get to be a significant added expense when upgrading video cards. One size simply can not fit all and here's why:
 The VID-280
"It combines a full gold-plated solid copper cooler which targets all primary heat-producing regions of the 8800GTS (including the voltage regulators)."
As one can see, VRAM, as well as GPU, and Voltage regs, are all cooled by this water jacket. And, there in lies a problem with video card waterjackets, one I'll come back to later. As each generation of card changes basic layout, they push the past water jackets into obsolescence. This can add $75.00 to a $100.00 dollars on to the price of a card upgrade. In short, if one wants a neatly packaged cooler that is specific enough to give proper homage to every heat source, one must except that is a marriage unto death. There is no re-using these things. Now that I think about it, I should have just glued it on! ":O}
So how does all of this come out on the business end?
This time around I decided to go with EVGA's card, price had much to do with it, but I've found EVGA to be a reliable supplier in the past as well.
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A bit about my set up
Motherboard: Asus Tech P5W DH Deluxe
CPU Type: dual core Intel Core 2 Duo E6600, 3600 MHz (9 x 400) (overclocked)
CPU Clock: 3603.9 MHz (stock speed: 2400 MHz, overclocked by 50%)
RAM: DIMM1: OCZ OCZ2SOE9001G 1 GB DDR2-800 DDR2 SDRAM (5-5-5-15 @ 400 MHz) (4-4-4-10 @ 266 MHz)
DIMM3: OCZ OCZ2SOE9001G 1 GB DDR2-800 DDR2 SDRAM (5-5-5-15@ 400 MHz) (4-4-4-10 @ 266 MHz)
Video Adapter: NVIDIA GeForce 8800 GTS 640MB, and driver by TweaksRUs
Disk Drive: Maxtor 6 L300R0 SCSI Disk Device (300 GB, 7200 RPM, Ultra-ATA/133)
Operating System: Microsoft Windows 2000 Professional SP 4
Case: Lian Li
PSU: Liberty 500 watt
 EVGA 8800GTS
I call it my "set up" as "Test bench" would lead one to believe that I might be attempting to publish definitive results. I'm not. Please read this only as a guide as to what the reader can reasonably expect from a similar system.
When I received my card I first installed it as is out of the box in order to establish base temps and give me the means to chart my progress. Like many before me, I was stunned. The card idles in my system at 50-55C running at it's native 576 Core 850 memory, depending upon ambient. (65-70F). The good news is that running it hard seems to little effect it's temps. As there are reviews available and my interests lies in watercooling I didn't push the stock card very much or very hard....Hey! I had a watercooler to install! ":O}
I setup to go to work on my card. The removal of the stock EVGA cooler was a walkthough. Following the Koolance instructions, and pretending I didn't know I was messing with a $500.00 investment, I can't afford to replace. I had to keep reminding myself that with reasonable care and precaution there was nothing "dangerous" about what I was doing... $500.00 WOW!
So with way more sweat than ambient can explain I marched on until... there were simply no more checks to my assembly or system I could make... again... without embarrassing myself... Time to do the deed...
By the way, if you're interested in acquiring this card... and I think you should be ":O} There is something you should know before you get one. These cards are advertised as requiring TWO slots to accommodates card and cooler. This is a lie! They require THREE SLOTS TO FUNCTION. There I said it. Why hasn't anyone else!? The 8800GTS from EVGA features the blower/heat pipe Nvidia reference design cooler. It looks a step up from previous coolers from reference, but it has what to me is a glaring flaw. Once installed, the blower faces the bottom of the case, which is to say the card immediately beneath it is less that a 1/4 inch off the blower... you can just see daylight! This maybe a perfectly acceptable arrangement at stock, but I would be very uneasy pushing things in this configuration.
Perhaps, someone reading this will post to forums and set me straight on how this works? Will people give up every slot in on their motherboard to run SLI? Because that IS what it will take to put two of these mothers in SLI with stock cooling... a small oversight from the people pushing SLI. I'd say.
The upside? The Koolance jacket takes up 14mm (about 1/2 an inch) of slot width space, an easy fit into a single slot.
Did I mention that water is a lot prettier than air? It is! It truly is! ":O} When you finally hit that button and cool clear water splashes its way out of the reservoir stalling then shooting the tubes to charge the system... it just does something to me, every time. I suppose I should mention that the above was included for it's emotive and literary value rather than as actual instruction on how to charge a water cooling system? ":O}
System charged, I take a few deep ones and kick-off. The final bubbles hiding out in dark places find their way to the clear tubes linking reservoir to CPU, CPU to GPU and back up to air purging reservoir, and vanish leaving micro bubbles to follow after them up my 3/8 inch tubes where they to vanish. And with their passing all evidence of motion within the connecting tubes leaves the water still seeming and blue with coolant. I check to see my dual pumps are running... (How many of you air coolers have a back up in place if a fan fails? Was that a cheap shot? Sorry. ":O}
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I head straight to the BIOS settings. CPU temps unaffected, so far so good! I boot to desktop and open Everest Pro to grab some system temps, I scroll down CPU, RAM. ah GPU... GPU... 64C! I shut down. I stare into my open case, which suddenly looks more like a patient in distress to me than an oasis of blue... what... could... I... have... possibly... done... so.... very.... wrong? I knew the card was safe as 64C is within it's operating temps... at max speed and very overclocked.... I reworked my work in my head a hundred times I knew I had never done a better assembly of card to jacket, I used guide pins so I wouldn't have to shift at all when card met the metal...it was right, less that a quarter of the screw hole off, and that's right ON! I went to bed and didn't cry, just whined about my fate a bit.
Next morning, I knew what I had to do. I emailed Koolance. Never hurts to talk to the guy that outfitted you when you get into trouble. I was told that this is actually quite common.and that there was an easy fix. It seems that as each manufacturer takes some liberty with reference design from Nvidia, getting the stand off pins which create the proper distance from all the desired contact points, hopefully without crushing any was problematic. In short, the pins were to long and preventing proper contact. It was explained to me that I should shorten the four pins surrounding the GPU. I look at my $500.00 dollar investment, I re-read the e-mail and visualized the procedure.
I would pull my card, dissemble cooler from card, look at the impressions left from the Thermal pastes and thermal pads, see where contact was lacking and file the standoff pins to fit. Then from out of the blue (I was staring into my case again) the old adage about the guy who wanted to shorten a table came to mind, he only wanted to take of an inch, but he had trouble getting the legs level and ended up with an uneven platform... "Send me some pins that fit please"
I went on to explain that I wasn't at all set up to do this job properly and if I was, due to past illness I no longer had the hands I once had for the finer things. To keep the cooler I would need extra Thermal pads and pins of the proper length. This GUY! He wrote back asking if I could send him my card and Koolance jacket and he would assemble it for me. Now just so everyone understands. This is not the way Koolance does things.This was just one person reaching out to help another, with Koolance's permission. If you buy one of these coolers please do not expect Koolance to assemble it for you. The level of difficulty seems low, but there are valuable things at stake should things go wrong at any point. Make your own judgment as to your skills and comfort with risk.
My card came back after an eternity spent on my wifes computer, I didn't care what temperature it ran at if it would just boot and let me sit at my own desk again! It had been 5 days! ( the week end, Koolance turned it around in two.) But as I opened the shipping box I started to care....":O}
Everything tubed in and system charged, I gain the desktop and read the temps
Ambient 75.7F
CPU at 3600 40C
GPU at stock 576 MHz core, and 850 MHz memory 39C
I weep with joy! After much , much messing about I settle on GPU 661 MHz and memory set to 1020 MHz as being proof against the climbing ambient as summer comes even at long last to Seattle. What does she idle at Overclocked? Why 39C of course! But I was able to heat the GPU to 45C when ambient hit 79.8. Running 5 consecutive 3Dmarks of followed by three 3Dmarks 03, I was drunk with the power to cool! I ripped open Aqua marks just to see them zip about like water bugs.
Like Overclockers every where I wait for winter. This card has yet to begin to bench. I was successful at 65F in getting a 168/140 to bench 3Dmarks, but with some artifacts, better ambient temps may help us out there. I've been asked sever times in the forums to comment upon the effect of adding a heat monster like the 8800 to my watercooling circuit.
The truth is I'm have a hard time diagnosing this. I think it minimal but there. But it only shows up after 75F and I just haven't had enough experience with this system in hot weather without a water jacket. VID-280 replaces my 7950 GT OC water jacket. My best guess is that the Exos II isn't a problem as it's rated to 750 heat watts. My case runs 3C above ambient, my water runs 2C above that. but at 79.8 I noticed that my case was only at 4.5C above ambient and that my ICH chip was at 47C (measure by next to chip probe.) So as temps go up, water temps go up, case temps go up, CPU and GPU temps all go up on their own unless cooled to compensate. So far I haven't found a direct connection, you see the card itself is so much hotter!
So I'll say this, I'm very happy with the set up. I'm miles ahead of where I could hope to be on air. I just don't have recent experience with other cooling systems to make a fair comparison. I am having to run my EXOS full out to maintain my overclocked system. Another difficulty is designed running temps. The 8800 doesn't even slow itself down until it hits 120C It was made to be bathed in heat.
My CPU cores on the other hand are always dancing just below temperature instability due to their overclocked state. I'm pretty sure I would have had to drop from 3.7 GHz to 3.6 Ghz at around 75F, with or without the card, but others are running 3.7 GHz and 3.8 GHz in the same temperature range and doing fine. So, no conclusions, just a few observations. Perhaps someone reading this will offer us better insight in the forums?
Buy the Koolance Exos-2 watercooling unit here. 
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