New Xeon CPU Hot and Underpowered

Kasracer writes "Web Sites The Register and GamePC received several of the new dual-core processors from Intel, dubbed 'Paxville', and ran a battery of tests on them. What did they find? From the article: 'There's no doubt about it, Intel's dual-core Xeons are their most power hungry Xeons to date ... Even when idling, two dual-core Xeons consume nearly 400W of power at any given time, which is amazingly high, even by Intel's standards ... their new dual-core chips (while powerful in their own right) simply are bested across the board by AMD's dual-core Opteron processors. Even worse, the Opterons typically perform much better while running at slower clock speeds and only having half the amount of on-die L2 cache to utilize.'"

Comments

This should change

[ottffssent]

The situation (Intel's, not necessarily the difference) should change RSN when Intel's 65nm process comes online. Looking at the huge lead AMD has right now, I don't see how Intel can beat them in both power and performance anytime soon unless they're willing to add a few hundred more pins to their sockets to accomodate on-die memory controller(s). I doubt Intel will do that. I also doubt they'll come back a bit from the 150W/CPU these Paxville chips crank out, so they'll be using the process headroom for higher clocks and/or larger caches.

Ultimately an on-die memory controller is the only way to bridge the increasingly large gap between the CPU and RAM. Intel's managed amazingly low latencies to RAM given that they've got an entire extra bus and chip to run through, but they're still ~50% higher than AMD's. The netburst architecture was supposed to be insensitive to RAM latencies but Intel is not keeping up in the bandwidth department either, and it's clear that these CPUs are suffering from a lack of RAM bandwidth (twice the processing power per chip, but no increase in bandwidth).

Re:This should change

[Anonymous Coward]

I'll give you a quick hint: the K8 (I.e. Opterons and Athlon 64 and X2 series) is a freaking marvel of technology. The dual-core variants even more so.

Intel's dual core chips are just two chips pasted on the same die. Take a look at a proper description of an X2 some time -- there's cache sharing, an inter-cache on-chip hypertransport bus and all that nice shit that Intel just doesn't have. It's not far-fetched to say that at the moment, speaking from a microarchitecture point of view, AMD is a generation ahead of Intel.

Re:Not terrible...

[masklinn]

Yup, power consumption figures are for the whole system.

But using roughtly equivalent systems (same power supply, an Antec TruePower so you're looking at an "at or above" 75% efficiency power supply when drawing 200+W from it, a single Raptor 74Gb and a Plextor DVD-RW drive), AMD's Opteron system top at 235W idle (for the 2.8GHz Opteron box) without using PowerNow's power management system (GamePC reports that the total power consumption @idle fell to around 170W using PowerNow) while Intel's 2.8GHz Xeon system chews through 390W idle...