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Cathar · 03-05-2004, 06:15 PM

You know, what would I give for a single solid piece of performance information that is not stacked to the gills with marketing hyperbolae?

What is the C/W of the block? I can roughly estimate it given what we've been told so far, and at 200ml/min, made of silicon (~150W/m-K), ~1.5mm thick base-plate, and even being generous and assuming a value for convection (h) of 250000W/m^2K, I arrive at an estimated C/W of around 0.25 for a 100mm^2 die, and that's not including the thermal goop/interface layer. Raising h to ∞ only improves that C/W by ~0.01. The use of silicon and the low flow rates seem to be the dominant sources of thermal resistance to me. If the silicon bp is really 0.75mm thick, then this knocks about ~0.06C/W off that figure.

I'd like to see how close to the mark my estimates are. I think it's quite telling that the marketing literature is full of hyperbolaic predictions, but quite short on actual hard information, which researchers of the calibre that the company is based on would obviously actually have and know, but they're not sharing it. Why?

You know, if I had something that was truly ahead of the game and wanted to push a hard sale, I'd have hard performance data right on the tails of the marketing material to back it up. If the block had a performance leading (BillA-style) T/W of 0.05, then why wouldn't they rush to make that public?

Excuse me for being cynical. Have read about twenty too many "Best....Performance....Ever" marketing material in my time.

03-05-2004, 06:15 PM	#19
Cathar Thermophile Join Date: Sep 2002 Location: Melbourne, Australia Posts: 2,538	You know, what would I give for a single solid piece of performance information that is not stacked to the gills with marketing hyperbolae? What is the C/W of the block? I can roughly estimate it given what we've been told so far, and at 200ml/min, made of silicon (~150W/m-K), ~1.5mm thick base-plate, and even being generous and assuming a value for convection (h) of 250000W/m^2K, I arrive at an estimated C/W of around 0.25 for a 100mm^2 die, and that's not including the thermal goop/interface layer. Raising h to ∞ only improves that C/W by ~0.01. The use of silicon and the low flow rates seem to be the dominant sources of thermal resistance to me. If the silicon bp is really 0.75mm thick, then this knocks about ~0.06C/W off that figure. I'd like to see how close to the mark my estimates are. I think it's quite telling that the marketing literature is full of hyperbolaic predictions, but quite short on actual hard information, which researchers of the calibre that the company is based on would obviously actually have and know, but they're not sharing it. Why? You know, if I had something that was truly ahead of the game and wanted to push a hard sale, I'd have hard performance data right on the tails of the marketing material to back it up. If the block had a performance leading (BillA-style) T/W of 0.05, then why wouldn't they rush to make that public? Excuse me for being cynical. Have read about twenty too many "Best....Performance....Ever" marketing material in my time.