IDF: Double-Pumped ALU?

GTaudiophile

Lifer
Oct 24, 2000
29,767
33
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While Intel clocked their Northwood at 3.5GHz, they ran through a pretty intensive demo with the CPU clocked at 3.0GHz. The presenters seemed surprised that they were actually up and running at 3.5GHz indicating an unexpectedly high yield on the part. We were slightly disappointed to find out that the system was supercooled but it does show off the potential of the chip. Later today Intel will be showing off an air-cooled 4GHz double pumped ALU (effectively 8GHz) from a future Intel processor. The interesting thing about this demo is that it will be a 32-bit ALU that's being shown off?

Anyone care to get technical and explain?

Read Article Here
 

bacillus

Lifer
Jan 6, 2001
14,517
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<< While Intel clocked their Northwood at 3.5GHz, they ran through a pretty intensive demo with the CPU clocked at 3.0GHz. The presenters seemed surprised that they were actually up and running at 3.5GHz indicating an unexpectedly high yield on the part. We were slightly disappointed to find out that the system was supercooled but it does show off the potential of the chip. Later today Intel will be showing off an air-cooled 4GHz double pumped ALU (effectively 8GHz) from a future Intel processor. The interesting thing about this demo is that it will be a 32-bit ALU that's being shown off?

Anyone care to get technical and explain?

Read Article Here
>>


there's another thread about this!
 

pm

Elite Member Mobile Devices
Jan 25, 2000
7,419
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The other thread is more specifically about the Northwood demo than the double-pumped ALU.

The Pentium 4 contains an ALU (Arithmetic Logic Unit - basically the section of the chip that does integer math functions) that is double-pumped meaning it is running at twice the clock frequency of the rest of the chip and thus can do two operations in a single core clock cycle. So a 2GHz Pentium 4 contains an ALU that is running at 4GHz internally. The Pentium 4's current ALU is only 16-bits wide, so rather than completing two independent operations per cycle, it actually produces one 32-bit set of data in two 16-bit internally-double-clocked clock cycles. The interesting thing about the demo that Anand mentioned is that it is capable of executing two independent ALU operations per clock cycle at an effective frequency of 8GHz.

Here's a brief section in an article by Paul DeMone. (link)
 

KpocAlypse

Golden Member
Jan 10, 2001
1,798
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What i find odd is this line....



<< The interesting thing about this demo is that it will be a 32-bit ALU that's being shown off? >>


What the heck is so "interesting" about that?
 

pm

Elite Member Mobile Devices
Jan 25, 2000
7,419
22
81
To me the 32-bit nature of the ALU is more interesting than the frequency. 32-bits wide is twice as wide as the current Pentium 4 ALU's. So that rather than being able to do one 32-bit operation per core clock cycle, you can do two in one cycle in this demo'd version.