First Look At Brookdale – Intel’s Upcoming 845 Chipset – THG.RU

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Introduction

Blue guys are using a vacuum cleaner and a golf club to remove light bulbs from an orange wall. What does that have to do with computer hardware? Well, I don’t really know, but I do know that this funky commercial is supposed to make us buy Intel’s Pentium 4 processors. If you look at the sales of this Intel’s flagship processor since its inception in November 2000 however, it seems rather obvious that the blue guys in front of the orange wall can suck as many light bulbs as they want. Motherboard makers can tell you that 5-10% of their motherboard sales are actual Pentium 4 platforms. The majority is still for Pentium III (i815, i810) and the rest of the boards hosts AMD processors.

I wonder if Intel’s wacky P4 television commercial is symbolizing what goes on in the brains of Intel’s decision makers. In medical school I learned about the effects of LSD and other hallucinogens, and the blue, white and orange stuff that Intel’s puts on our television screen seems to be rather close to the visual experiences you have after heavy consumption of the just mentioned drugs. Let’s be honest, what else could possibly explain Intel’s recent decision to launch a ‘value’ Pentium 4 chipset that chains its ‘netbursting’ super processor to the good old PC133 SDRAM memory? Crack pipe or what?

‘Brookdale’ or i845

You have certainly noticed it by now; I am talking about the upcoming i845 chipset (formerly known as ‘Brookdale’) that stole the show of everything else at the recent Computex 2001 in Taipei. It is common knowledge by now that this chipset is also supporting DDR-SDRAM, but Intel is unwilling to release i845 plus DDR anytime soon. In August we will have the chance to build nice and clean RDRAM-free Pentium 4 systems, but instead of the obvious alternative DDR-SDRAM, we will have to use PC133 SDRAM. It is not very hard to imagine that this slightly outdated and somewhat slow memory type will have a major performance impact on Pentium 4. The question is only how much of an impediment PC133 memory will be for Pentium 4.

Let have a look at some of the facts:

The table shows that PC133 is the oldest of the three currently available memory types on the market. It comes with the lowest bandwidth, though with the lowest (and thus best) latency as well. PC133 is very inexpensive, but the price advantage over the more advanced DDR-SDRAM is shrinking daily and does not play a major role in cost considerations anymore.

One-channel SDRAM configurations, such as in case of the upcoming i845, can only provide a third of the bandwidth of current Pentium 4 platforms with i850 chipset. From that point of view it seems very likely that i845 will starve Pentium 4 for data. However, we know from Pentium III systems that PC133 is able to outperform RDRAM if the bandwidth doesn’t come into play, because RDRAM’s latency is so much higher than that of PC133 SDRAM that the PC133 i815 platform is able to outperform the RDRAM chipsets i820 and i840.

The Right Memory Type For Pentium 4

Pentium 4 likes high bandwidth or it can at least take advantage of it, due to the high bandwidth of its processor bus. The 100 MHz clocked and quad-pumped P4-bus has a bandwidth of 3.2 GB/s, which is just as high as the dual-channel RDRAM memory configuration of the i850 chipset. The 1 GB/s of i845 with PC133 SDRAM are significantly less than what Pentium 4 would be able to compute, which is why even the very low latency of PC133 won’t be able to make up for it.

Unfortunately it has become common belief that Pentium 4 was ‘designed for RDRAM’. This is of course nonsense. Intel would be rather crazy if it would indeed design its processors for one particular memory. RDRAM memory would be a extremely bad choice, since its acceptance in the market still remains very low, partly due to Rambus unethical actions of listening to ideas in JEDEC-conferences and then patenting them as their own inventions and milking JEDEC members with demands for license fees.

Pentium 4 has been designed for high memory bandwidth. This can also be provided by DDR-SDRAM and especially by dual-channel DDR solutions as just realized by NVIDIA in form of the nForce chipset. We will see that Pentium 4 suffers from the low performance of PC133 SDRAM. However, the story might well be very different with DDR-SDRAM. Industry sources are already talking of the superior performance of i845/DDR solutions in some applications, while others claim that VIA’s upcoming P4X Pentium 4 DDR-chipset will outperform i845/DDR as well as i850. I won’t believe that Pentium 4 ‘requires’ RDRAM until I have seen it with my own eyes. So far Intel is trying its hardest to ensure that RDRAM does indeed remain the best performing memory type for Pentium 4. However, sooner or later someone will run Pentium 4 with something that is faster than PC133 memory. We will see if RDRAM will remain the best P4-memory then.

Antichrist Rambus Reason For i845/DDR Delay?

The i845 chips that are available to motherboard makers right now do not just support PC133 SDRAM. They are already coming with full-blown DDR-SDRAM support, but Intel does not want any i845/DDR platforms to ship before January 2002. Several people have speculated that this is due to Intel’s deal with Rambus. However, as appealing as those speculations may be, I doubt that Intel will intentionally jeopardize Pentium 4 sales for a petty agreement with naughty Rambus, the memory Antichrist. If Pentium 4 plus RDRAM doesn’t sell well, then Pentium 4 plus PC133 will sell even worse. The latter combination may be less expensive, but its performance is dangerously close to what current or near-future Pentium III platforms are able to offer. Pentium 4 needs DDR-SDRAM support and Intel cannot be that much on drugs that is wouldn’t realize it.

THG’s i845 Test Platform

Unfortunately we cannot disclose who made our i845/SDR platform, but the manufacturer will know and I’d like to take the chance and congratulate him and of course Intel for providing an extremely stable and reliable chipset/motherboard combination. It was also a good proof for the fact that this board is ready to ship and not much of a pre-release board anymore. We ran our fastest PC133 SDRAM in it and adjusted the memory settings to 2-2-2-5/7 to squeeze the last bit of performance out of it. The motherboard happened to be a typical i845-solution with the upcoming Socket478, which will soon replace the current Socket423. The new socket is much smaller than the current Pentium 4 socket and it requires different heat sinks as well. Socket478 will be able to host the next-generation Pentium 4 with ‘Northwood’ core, which will be introduced in a few months at speeds of 1.9 and 2.0 GHz. Owners of the older Pentium 4 version for Socket423 might find a few transitional i845-motherboards that host their old processors, but those boards won’t come with any upgrade paths for the new Northwood Pentium 4 processors anymore.

The north bridge of i845 reminds of Pentium III and requires a heat sink for proper operation. It hosts the Pentium 4 interface, the AGP-controller, capable of 4xAGP and the SDRAM/DDR-SDRAM memory controller. It is connected to the south bridge via the well-known 8-line hub-architecture link that’s running at 266 MHz.

THG’s i845 Test Platform, Continued

The south bridge is surprisingly marked with ‘secret’, although it represents the well-known ICH2-chip that we can already find on i850 boards. It’s revision level was ’12’, while current ICH2’s come with revision level ’02’. Still, the features were identical to those known from i850-boards. The shortness of time for this review kept me from digging into the differences between the two ICH2-revisions.

The chipset-inf software was provided, so that the installation under Windows 9x and Windows 2000 was a piece of cake. WCPUID 3.0b is not yet able to recognize the chipset.

Pentium 4 For Socket478

The processor we used for testing was a 1.7 GHz Pentium 4 with Willamette core, even though the new form factor may make you believe it was a ‘Northwood’. Please note the significant difference in size between the old and the new model.

Socket mPGA478 is of course also much smaller than Socket423 and the pins are much closer together than in the previous socket. The retention mechanism has not changed, but due to its small but clumsy shape, it is a bit fiddly to take the new Pentium 4 out of Socket478.

Pentium 4 For Socket478, Continued

WCPU 3.0b was not able to recognize the processor as a Socket478-version.

However, MadOnion’s 3DMark2001 reported the right socket.

Cooler manufacturers will be pleased to know that Socket478 requires differently sized coolers. The new retention mechanism is completely different to current Pentium 4 coolers and the shape of the cooler is slightly different as well. The new cooler needs to be shorter, but wider.

We cooled with an old P4-cooler after removing the new retention frame that you can see above.

Expectations

Nobody will be surprised if i845 plus PC133 won’t be able to reach the scores of i850 plus RDRAM. The question however is, how much of a performance decrease we will actually see. Applications that rely on high memory bandwidth will suffer, while applications that require short latencies might not perform much worse than on i850.

I also threw my recent Tualatin-results into the equation to see if Pentium 4 plus i845 and PC133 SDRAM is still faster than Pentium III Tualatin. If the latter should not be the case it is very difficult to see a major sense behind the existence of i845/PC133.

Test Setup

Sysmark 2001 under Windows 98

i845/PC133 is some 7% behind the result of i850/PC800 in the office and internet application benchmark Sysmark2001. The Pentium 4 1.7 GHz used with i845 is just able to reach Athlon 1200 scores. At least Pentium III Tualatin at 1.13 GHz is still outperformed by both Pentium 4 platforms.

The ICC-part of Sysmark2001 is the strength of Pentium 4 and the i845/SDR-solution is just about able to score Athlon 1400 results, while lagging almost 10% behind i850/RDRAM with the same processor.

Office productivity is where Athlon easily outperforms Pentium 4. The i845/PC133 is 6.5% slower than i850/PC800, but both are even slower than Athlon 1200.

Sysmark 2001 under Windows 2000 Professional

Under Windows 2000 the difference between i845/PC133 and i850/PC800 is larger. The ‘value’ SDRAM-platform lags some hefty 11% behind the scores of Pentium 4 with RDRAM. Athlon 1400 is also easily beating Pentium 4 with i845 and SDRAM.

In Internet content creation i845/PC133 is still able to beat Athlon 1400, but it scores 12% worse than i850/RDRAM.

In office productivity i845 lags behind i850 once more, while Athlon 1400 scores the highest results.

Summary Internet/Office Performance

All in all i845 with PC133 SDRAM costs about 7 – 12 % performance compared to i850 with PC800 RDRAM. This is huge, as it puts Pentium 4 1.7 GHz in the area of a Pentium 4 at 1.4 – 1.5 GHz on i850 or an Athlon 1200/133.

Quake 3 Arena

In Quake 3 the performance of i845 with PC133 SDRAM can only be declared as rather sad. The new Pentium 4 chipset scores no less than 23% worse than i850. Tualatin 1.13 GHz is almost able to reach those scores, while an Athlon 1200 beats Pentium 4 1.7 GHz w/i845 hands down.

The sad story remains. Intel’s upcoming i845 chipset with PC133 SDRAM is 23.2 % slower than i850 with PC800 RDRAM and gets beaten by Athlon 1400 as well as 1200. Tualatin 1.13 GHz cannot quite reach the i845 score, but it gets pretty close.

Unreal Tournament

UT has never been a strength of Pentium 4. Athlon 1200 is already scoring better than Pentium 4 1.7 GHz with i850 and RDRAM. The solution with i845 and PC133 SDRAM scores another 16% lower and is therefore really not interesting anymore.

Dronez

Dronez is an example for the new breed of DirectX8 games. It comes with enhancements for Pentium 4, which results in better scores of Pentium 4 1.7 GHz with i850/RDRAM than Athlon 1400. However, i845/PC133 impacts Pentium 4’s performance so badly, that it scores worse than Athlon 1200 and almost 24% worse than Pentium 4 with i850/RDRAM. Only Tualatin 1.13 GHz scores even lower results.

AquaNox

AquaMark runs usually better on Athlon than on Pentium 4 anyway, but with i845 Pentium 4 performs like a dog, scoring 18% worse than the i850/RDRAM platform.

3DMark2001

While Pentium 4 1.7 GHz with i850/RDRAM scores pretty much the same results as Athlon 1400, i845 with SDRAM is able to make Pentium 4 1.7 GHz perform 18% worse.

Summary 3D Gaming Performance

The average performance loss of i845/PC133 vs. i850/PC800 is almost 21% and therefore unacceptable. 3D gamers should rather go for the more attractive Athlon-solutions unless they want to spend the big bucks for Pentium 4 plus RDRAM.

Sandra Memory Performance (STREAM)

This benchmark shows that the memory performance of i845 with PC133 SDRAM is about 50% of i850 with PC800 RDRAM. However, it is surprising to see that i845 doesn’t score much worse than Athlon with AMD760 and PC2100 DDR-SDRAM in this test.

FlasK MPEG Video Encoding

Although Pentium 4 1.7 GHz with i845 is losing 20% versus i850, it still remains well ahead of Athlon 1400. This is obviously due to the hand-coded SSE2 implementations. It shows however, that memory bendwidth isn’t the whole secret behind those benchmark scores.

SPECviewperf 6.1.2

SPECviewperf is another highly memory sensitive benchmark, that shows a performance delta between i845 and i850 of up to 28% in DX06. I guess it is obvious that you shouldn’t use i845 for professional OpenGL-stuff.

Conclusion

There we are. The first look at Intel’s initial version of ‘Brookdale’ the ‘value’ Pentium 4 chipset i845. The question now is, who will be interested in it? It is true that it will make Pentium 4 much more affordable due to its PC133 SDRAM support, but its lackluster memory performance impacts Pentium 4 so badly, that it makes AMD’s Athlon an even more attractive solution than it already is. I also don’t expect board prices to be that low, since Intel has a long high-price history for its chipsets, even when they are carrying the ‘value’-tag.

I personally would consider everyone as close to crazy if he should choose Pentium 4 plus i845 and PC133 SDRAM. Intel will try to use the blue men and the rest of its marketing machine to capitalize on the Pentium 4 nametag for i845-systems. However, this sad performing solution is just another sign that Intel is running out of ideas. I have to say that I am more than tired of half-baked solutions that are sold as new products.

Why does nobody at Intel have the guts to come out with the obviously functional i845 for DDR? Pentium 4 sales are far from great right now and I don’t see how i845 with PC133 is supposed to change that. Intel will continue making a fool out of itself if it continues to hold on to the sinking Rambus ship instead of showing some guts and release i845 with DDR-SDRAM. Dear Pam Pollace, please spare us with even more ‘Blue Men’ commercials that try to sell i845 to the poor uninformed masses, and tell your bosses that they should try coming up with reasonable products instead.

The i845 is not a bad chipset. Once it is teamed up with DDR-SDRAM it will most likely be what most Taiwanese motherboard makers call it: the new ‘BX’. However, as long as Intel keeps the DDR-version from us, I wouldn’t even touch an i845 motherboard.