It has been about 4 months since we reviewed the Pentium 4 2 GHz processor. Until January 7th 2002 that was also the fastest clocked processor in production, but not anymore. On the same day AMD brought out their Athlon XP 2000+ (clocked at 1.67 GHz) Intel brought out a 2.2 GHz part as well as an updated 2.0 GHz one (called 2.0A to signify it features a new core).
So what's new apart from the higher speed in the Intel 2.2 GHz and 2.0A GHz ? Well, we're not talking groundbreaking changes, but definitely enough to make it worthwhile covering!
The new Pentium 4's are based on a new core called "Northwood". The earlier P4's (the one we reviewed) was based on a different core named Willamette. Below I will highlight some of the changes that have taken place. For those interested in other architectural Pentium 4 specifications (which haven't changed), check out our earlier review of the Pentium 4 2 GHz here).
From left to right: P4 2.0 GHz, P4 2.0A GHz and P4 2.2 GHz (Click to enlarge)
From left to right: P4 2.0 GHz, P4 2.0A GHz and P4 2.2 GHz (Click to enlarge)
As you can see from the above pictures, the new 2.2 and 2.0A GHz Pentium 4's are exactly the same size as the original Pentium 4 2 GHz. It features the same packaging as the earlier Pentium 4 2 GHz (socket 478) and includes an integrated heat spreader as well. The bottom shot does however show that Intel has put on a few more transistors. Exactly what they are for, I'm not sure, though.
From left to right: P4 2.0 GHz, P4 2.0A GHz and P4 2.2 GHz (Click to enlarge)
So, no big external changes.
On the inside, however, things have changed:
The Northwood - Core Changes! First of all, Intel decided to change its manufacturing process and are now using copper for the Northwood cores as opposed to aluminum that the Willamette featured. On top of this (or as a result of this) it has allowed them to shrink the die size from 0.18-micron to 0.13-micron, something that has resulted in significantly lower power consumption, lower heat output and lower production costs overall. The shrinkage of the die makes the core almost 30% smaller than the Willamette version, which obviously mean they can make more processors from the same size silicon than was earlier possible.
Power consumption and core voltage The lower power consumption means that Intel has managed to get the core voltage down from 1.75v to an impressive 1.5v. That in its turn has led to lower heat output. The Willamette Pentium 4 2 GHz's heat output was rated at 72W whereas the Pentium 4 2.0A GHz is rated at 49W (and the 2.2 GHz at 55W). If those numbers hold true (they are official Intel numbers) it will mean that Intel will be able to produce the Northwood core with much higher clock speeds than the Willamette core allowed for. I have seen figures that say that we can expect to see 3.0-3.5 GHz parts with this core. I can't confirm these numbers. We can only wait and see - in real terms the processor is actually running a great deal cooler. Probably a 5-8 degrees C cooler overall. The heatsink definitely feels cooler to touch too.
AMD has still to put 0.13-micron processors on the market. This gives Intel an advantage as they can provide higher speed processors at a lower cost than AMD and processors that run a lot cooler. AMD are however currently working on 0.13-micron processors, but have yet to launch them to the mass market.
L2 Cache The Northwood core now features 512kb of L2 Cache compared to 256kb on the Willamette Pentium 4. This is something that became possible due to the shrinkage of the processor core. A doubling of L2 Cache should have a positive effect on CPU performance as it becomes somewhat less dependent on external (and slower) RAM sources.
Price The Pentium 4 2.2 GHz processor is selling for around $500 USD and the 2.0A GHz for around $350 USD.
Platforms Since our review of the Willamette Socket 478 Pentium 4 2 GHz a much wider array of chipsets and motherboards have become available. To combat the high costs of RDRAM, which made the Pentium 4 unreachable for many people in the beginning, Intel decided to bring out platforms for other - and cheaper - RAM types. First out was the i845 platform with support for SDRAM (PC133) and recently an updated version with support for DDR RAM. VIA and SIS wouldn’t be left in the dust, so they have brought out chipsets for the Pentium 4 with support for DDR RAM as well. The options for consumers are much greater – and cheaper – than before.
The processors for this review were delivered with Intel's D845BG i845 based DDR SDRAM motherboard. As I had Epox' 4BDA2+ in the lab too, I decided to go with that one instead. The reason for this is that it has nicer features, amazing overclocking options and good stability overall. I have decided to use Abit's TH7II-Raid, which uses RDRAM, in this review as well as it shows what the Pentium 4 really goes for... if you can afford it! Overall, the i845 DDR platform is much better than I thought it would be. The numbers are good overall.
