Please, this is not a cynical attempt for promotion. I just want to share/ask people if they've got any ideas as to what's going on here.
If you're not familiar already, recently some kind individual managed to source some pure silver to make a few of
these blocks.
Okay, so I've done some temperature comparisons between the copper Cascade and the silver Cascade, and basically the nod goes to the silver Cascade to the tune of just over 0.5C (best that I can determine) given my test CPU heat load.
What was weird to begin with though was when it came to overclocking. I must've mounted the copper Cascade onto this CPU (AMD Barton XP2800+) maybe 20-25 times in the last 2 months, and compared it to a number of other highly respected commercial blocks. In all cases the copper Cascade came out ahead of the other blocks both in terms of overclocking potential and temperature. The White Water came in a tied second with another commercial block (which is a lot more expensive than the White Water) being about 2C and 15-20MHz behind the Cascade.
Okay, so I've run dozens of tests and have a pretty good idea of where things stand in relation to each other, and the silver Cascade is an "in theory matching reality" predicted ~0.5C better than the copper Cascade.
That is until I tried to overclock. I had never been able to achieve greater than 2680MHz Prime 95 TT stable with the copper Cascade and the Barton. The machine could boot into WinXP at 2695MHz, but was unstable and would constantly restart the "Explorer" interface, so basically it was good enough to take a quick screen-shot and that was it.
With the silver block I was able to hit 2720MHz Prime95 TT stable and had issues getting the machine stable above that point "at all". Almost like a razor-fine line had been drawn in the sand with respect to stability/bootability. If I tried any higher, the system failed to make it into Windows and sometimes wouldn't even POST.
That was, until about 2 hours ago. Just browsing the web and glanced at the CPU temperature and it was about 3.5C lower than where it had been sitting at for the last 4 days of testing with the silver block. Nothing had changed with the system, and the room temperature (and correspondingly the water temperature) was slightly warmer than "normal" as I've got the flu and have gotten the heater turned up a bit.
Okay, it's just a thermistor error is my first reaction, but hopeful, I try to overclock past 2720MHz....and it works!
I'm now typing this at 2737MHz with Prime95 TT running in the background. I tried at 2749MHz and it booted into WinXP just fine and even ran Prime95 TT for a few minutes before failing, so I dropped back to this speed.
I am totally weirded out now, because this is something I've never ever seen or experienced the likes of before. A ~60MHz overclock gain is something I would have never ever though possible.
I have a theory though, and here we get to the point of the post (finally). The block is made out of pure silver, which is fairly soft and deformable in comparison to copper. Pure silver almost reaches the levels of pure gold in terms of softness. You can bite it and leave an indentation and it scratches pretty easily. The silver plate is thick enough and strong enough, however, to not flex under mounting pressure (which is about twice the AMD recommend maximum pressure at present), but that doesn't mean that the base-plate hasn't micro-scopically deformed to more closely mate with the CPU's surface.
Is such possible? Could this be the explanation? Is perhaps the next step for better thermal contact actually the use of soft deformable metals as base-plate material?