More Super Cool Overclocking

octools.com has a followup to a story we linked there a couple of months ago where they submerged a motherboard in nitrogen cooled flourinet, and overclocked the hell out of the chips. Well, they're back with an extensive photo documentary of the sequel where they try to take it below zero, and clock things over a gigahertz. You probably shouldn't be trying this at home, but it sure is fun to see on a Web page.

Re:Who Cares?

The fact remains that the cpu's that most overclockers use are very cheap in comparison with the latest high end chips. For a few extra dollars spent on a good motherboard and a Golden Orb cooler overclockers are safely pushing 600 MHz Celerons to 850 Mhz and beyond. With this sort of price for performance, one might ask, "Why wouldn't you overclock?"

That said, this article was obviously done just for the sheer geek of it and power to them. The advances in cooling could easily be used in future production machines.

If you have to ask "Why overclock?" then you are obviously not the type who takes every new toy in your home apart as soon as it comes in the door just to see how it works and how you can screw with it.

Gotta cool it all?

IANAOC. Seems they had success when everything was uniformly cooled with the Flourinert and dry ice. Problems arose when they used the Liquid Nitrogen on JUST the processor. So, the CPU could go faster than the support chips which were not similarly cooled? Maybe the video card, though now running with the same bus speed as the LN-cooled CPU could not operate at those speeds without also being cooled to LN temps. They mentioned:

So what happened? Did it boot? Yeah it did. Booted easily with the CPU at about -150C(block temp), but you cannot understand the language anymore. The screen suddenly turned alien into us. We cannot understand a damn thing! Checksum error was up. We could go into the BIOS but everything was different. The keyboard types different letters.

CPU could handle it okay, but the rest of the system was breaking down. Gotta cool the WHOLE thing, or else your system is only as fast as your slowest link.

So, for MISSION: SUBMERSIBLE 3, I'd like to see them try immersing the ENTIRE RIG in LN, with good-sized heat sinks on the CPU, video card... everywhere and THEN see how it worked. The major concern I'd have would be they migh be encountering a race condition between components that would never arise at conventional speeds.

Offtopic, but here's an idea of what they could have done with the LN when they were done with THAT experiment. (I attended a party in college where we actually DID this. IIRC, It was some time around 1979 or 1980.) Use the excess LN to freeze some vodka in ice cube trays! The vodka will easily freeze at those temps... voila! VodCubes! Take a couple VodCubes, drop 'em in a cup of collins mixer, wait for the VodCubes to stop dancing around on the comparitively hot collins mixer, and enjoy your vodka collins! Looking back, I wish we had tried it with orange juice -- could have called it a frozen screwdriver!

Limitations on overclocking

Recently, in one of my EE courses, overclocking was mentioned. It was also mentioned why certain designs can only be pushed so far, and after that they cannot be clocked any higher, regardless of how well they are cooled.

The problem is with propagation delays. Basically, when one part of a digital logic circuit goes high or low, this change takes time to propagate to the rest of the circuit. This is a very small delay, but when you have a circuit as complicated as, say a Pentium III, it can become important. There are small gaps in between parts of the circuit being in different states, and as the clock rate is pushed higher and higher, these gaps become smaller and smaller. If the clock rate is pushed too high, different states of the circuit will overlap, essentially causing it to malfunction. It should be noted that a circuit or portion thereof does not change states (0 to 1 or 1 to 0) instantaneously; this is what allows the overlap that ends overclockability. Propagation delays also explain why, for example, you can't push a C64 to 200 MHz. The circuits in the CPU weren't designed for speeds like that.

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In case you missed the point completely....

it's not about seeing if a chip can break the 1 Ghz barrier. Off the shelf crap can do that. It's about make stuff perform well beyond its rated capacity -- about testing the limits. It's about doing something funky for an afternoon that hasn't been done much before.

This may be a bold comparision, but if Sir Edmond Hillary's accomplishment was posted on /., how many people would say "Why did he do that? There's nothing at the top of that mountain. That's dumb. He could have flown over it. What a moron."

cost

Over a year ago I spent about $400 building an overclocked dual celeron system. It has two C333's running comfortably at 500mhz with no problems at all. One year later its still faster than most systems available today. Lets see you beat that price/performance factor. It sure was funny seeing intel developers stating that celerons don't support SMP while abit was cranking out BP6's left and right.

Here's what REALLY happened

So what happened? Did it boot? Yeah it did. Booted easily with the CPU at about -150C(block temp), but you cannot understand the language anymore. The screen suddenly turned alien into us. We cannot understand a damn thing! Checksum error was up. We could go into the BIOS but everything was different. The keyboard types different letters.

Some scientists think that as you approach Absolute Zero, time starts to slow down, just like time slows down as you approach the speed of light.

So based on the extremely low temperatures, and the extreme amounts of electricity involved. I believe that their computer had actually jumped forward in time!!! Those strange characters on the screen were really future space alien types trying to communicate! How else could you explain this line here:

The screen suddenly turned alien into us

Next: the supercooled backpack.

I'm going to seal my backpack and fill it up with LN2. This will allow me to keep my Journada supercooled, and I will be able to take it out and get crazy framerates in Doom!

If I have thick enough gloves, I should be fine.

This plan has several added benefits: I can always have supercooled Pepsi with me and if I say an extremely attractive female and start to lose control of myself, I can just dump my backpack over my head and be cooled off.

crack... crack...