The Intel Pentium II (‘Klamath’) CPU – THG.RU

Introduction

The upcoming Intel Pentium II (‘Klamath’) is meant to be the successor of the well known Pentium Pro. It will be released on the first days of May but fortunately we’ve already got quite a lot information about the new Intel CPU flagship now. Amongst other things, the Pentium II (‘Klamath’) is meant to cure the huge problems of the Pentium Pro with 16 bit code. This 16 bit weakness has so far been the reason for the quite poor success of the Pentium Pro.

As you can see, it will not fit into the Pentium Pro socket 8 and for the beginning it won’t even go in any socket at all, since Intel will sell it as a unit together with its external cache in form of a slot card for the new ‘Slot One’. It will come with the new MMX multimedia extension to its instruction set, just as the Pentium MMX and it will be released as a 233 and a 266 MHz version to start with.

Now what is it all about with the new Pentium II (‘Klamath’) and what can we expect from this new Intel CPU?

Facts about the Intel Pentium II (‘Klamath’)

• The Pentium II (‘Klamath’) doesn’t include any second level cache anymore as its predecessor the Pentium Pro did. This is due to production costs, since in case only one portion of the die in the Pentium Pro (the CPU core or the L2 cache) is not functioning in the post-bonding CPU tests, the whole CPU has to be thrown away. The chips can only be tested after the bonding and at this stage it’s too late to use one of the two components anymore.
  External L2 cache means less L2 cache performance. The Pentium Pro runs its internal L2 cache at clock speed, the Pentium II (‘Klamath’) will run its external special BSRAM (burst static RAM) cache only at half the clock speed, which makes this cache considerably slower than in the Pentium Pro.
• The external bus speed of the Pentium II (‘Klamath’) will still be only 66 MHz, the bus speed we know well from Pentium and Pentium Pro CPUs. Obviously Intel doesn’t seem to plan higher bus speeds before the release of the next CPU, the Deschutes.
• The Pentium II (‘Klamath’) will come on a slot card for the new so called ‘Slot One’ motherboard slot. We all expected it anyway – we will need new motherboards for the Pentium II (‘Klamath’). On this slot card there will be the L2 cache as well, which is planned to be 512 and later also 256 kB in size. Intel is planing to later on sell the Pentium II (‘Klamath’) without the slot card to some few selected OEMs. The old Pentium Pro can also be used on these new boards, via a special CPU card with a Socket 8. This CPU card can be manufactured by motherboard manufacturers, but they’ll have to pay a considerable price for each card, since the ‘Slot One’ is patented by Intel.
• The CPU speed of the first Pentium II (‘Klamath’) will be 233 MHz and 266 MHz models will be following soon. This makes a multiplier of 3.5 x 66 MHz for the 233 version, with a multiplier of x1.75 for the L2 cache, and 4 x 66 MHz for the 266 MHz version, with a L2 cache multiplier of x2. On some exhibitions Intel has shown a Pentium II (‘Klamath’) at 300 and once even at 400 MHz (water cooled), but it’s unclear at which speed the level 2 cache was running then.
• The Pentium II (‘Klamath’) will now have segment register caches, which will improve the poor 16 bit performance known from the Pentium Pro. Hence the Pentium II (‘Klamath’) will run 16 bit programs and mixed 16/32 bit OSs like Windows95 somewhat faster than the Pentium Pro.
• The first level cache of the Pentium II (‘Klamath’) will be increased to 16 kB data and 16 kB instruction cache. The Pentium II (‘Klamath’) will have more write buffers as well. These two things increase the L1 cache performance of the Pentium II (‘Klamath’) and help reduce the Pentium II (‘Klamath’)’s disadvantage of its slower external L2 cache.
• Due to fewer production costs, the Pentium II (‘Klamath’) could be even cheaper than the Pentium Pro. However, we’ll have to wait for its release to be sure about this. I personally doubt this!
• Read the latest news about Pentium II (‘Klamath’) pricing and availability and Pentium II (‘Klamath’) voltage requirements!

Pictures of the Intel Pentium II (‘Klamath’)

Front

On this side there’s a huge heat sink mounted on top of the CPU, which is covering the whole surface of the CPU card. It’s mounted via the four holes around the CPU and kept with these two springs you can see below.

Back

The Performance of the Intel Pentium II (‘Klamath’)

Eventually I’ve also been able to do my own tests with the Pentium II. The CPU I got was actually brought over by Mr.***. Mr.*** made a special trip from ???? to bring me the CPU and unfortunately he had to take it with him in the evening when he left. We didn’t have the time to do benchmarks under Windows NT, but I’ll publish his results, so that you’ll get the picture.

The board I used was a board I can’t name with 64 MB of Crucial Technology 50ns EDO RAM. This is the first board for a Pentium II I received. As with all the new boards for Pentium II CPUs it comes with this ‘Slot One’ called CPU slot to plug in the Pentium II CPU card. If you want to use a Pentium Pro, you’ll need a special CPU card with Socket 8, which you can plug into the ‘Slot One’ instead of the Pentium II. This CPU card is licensed by Intel and hence each motherboard manufacturer has to pay a fee to Intel for being allowed to produce this CPU card in license.

The board I can’t name comes with a feature that is now well known, but also cannot be named. This particular feature recognizes the CPU very well. It recognized my Pentium Pro as well as the ‘Klamath MMX’ CPU without any problems. For each CPU you can choose between 150, 166, 180, 200, 233 and 266 MHz CPU speed and you also have another unameable feature to tweak the performance of the CPU a little bit more. The board was equipped with an ‘Evaluation BIOS – Not For Sale’, which did not include the ‘write combine’ MTRR setting for the video card’s linear frame buffer. This feature is included in all later Asus boards for Pentium Pro CPUs and will hopefully be included in the tested motherboard’s release version of the BIOS. To enable this important feature I had to use ‘fastvid’ or ‘ctppro’.

To be fair to the Pentium Pro as well as to the Pentium MMX I tried to run each CPU at almost the same clock speed. This is the best way to show how the architecture of each CPU compares to the others. The Pentium Pro 200 runs absolutely well at 233 MHz and doesn’t get as hot as the Pentium II at all at this clock speed, despite the huge Pentium II (Klamath) heat sink. I actually had to mount a fan on one side of this mega-heat-sink, because otherwise you wouldn’t be able to touch it. This Pentium II (‘Klamath’) CPU gets hotter than any Cyrix 6×86 ever got.

The test configuration was as follows

• Pentium II (‘Klamath’) running in a board I can’t name at 233 MHz
• Pentium Pro running in the same board I can’t name with a special Socket 8 ‘Slot One’ card at 233 MHz
• Pentium MMX running in AOpen AX5T at 225 MHz
• Matrox Millennium, BIOS 2.3, Driver 3.22 for all tests, Windows 95 screen resolution 1024×768, high color (16 bit), 75 Hz refresh rate, only 8 bit color for Intel Media Bench

The results of the Pentium MMX can even be topped by increasing the CPU speed to 250 MHz. In this case the Pentium MMX is the fastest CPU under Windows 95, which I’d consider as quite surprising. I’ve also tried to run the Pentium II (‘Klamath’) at 266 MHz, but it crashes after a few minutes. The PPro also doesn’t run reliably at 266 MHz.

In each table I’ve marked the best results with a light red background. I think you’ll be quite surprised and most likely be fairly disappointed about the results

DOS Performance

Unfortunately I wasn’t able to run Quake with ‘write combined’ linear frame buffer. Without this feature the result is very low. As soon as I enabled write combining, Quake would crash as soon as I switched to a VESA mode. The results of the non-VESA modes are fairly different to the VESA mode results. In these low resolution modes the Pentium MMX is definately the fastest CPU. This is not valid for the VESA modes, where the write combining of the Pentium Pro and Pentium II enhances the transfer to the linear frame buffer considerably. Fortunately the PC Player Benchmark ran with enabled write combining and it shows that the Pentium II is slower than the Pentium Pro as well. The good old 3DBench is just amazingly fast with a Pentium Pro and Chris Dial’s 3D Bench is also still ruled by the Pentium Pro.

This comparison shows very well which is the best DOS games CPU. It’s funny but true – the Pentium Pro is “THE” best game CPU currently available and this even though DOS is just a 16bit OS.

For DOS games there’s NO POINT for the new Pentium II.

Windows 95 Performance

Well, you can see the results yourself and now please tell me you’re not disappointed. The Pentium II (‘Klamath’) is a little bit faster in the business graphics and hence in the Business Winstone as well. It still doesn’t reach the 16bit performance of the Pentium MMX at all and it’s 32bit performance is less than the Pentium Pro as well. Now please somebody give me ONE reason to be keen on this new CPU.

Again NO POINTS for the Pentium II !!!

Windows NT Performance

Mr. *** was using a different board for his testing which had serious trouble with PCI devices. Therefore he tested with an ISA video card, so don’t be surprised about the low Winstone results. They have been getting cold feet now, so I removed the results. The markings still show which CPU was faster.

Windows NT has always been the domain for the Pentium Pro. It’s internal L2 cache and the 32 bit code enhancing architecture were the reason why this CPU has been the best Windows NT performer. It was expected that the Pentium II (‘Klamath’) would have his toughest time here in defeating the Pentium Pro. The expectations were more than fulfilled. If it wasn’t for the MMX enhanced image processing software, there wouldn’t be any reason for a NT user to get a Klamath instead of a Pentium Pro.

The smart Windows NT user frowns and gives absolutely NO POINTS for the Pentium II.

MMX Performance under Windows 95

I can’t help but wonder about these results as well. We all expected a clear lead of the Pentium II (‘Klamath’) at least in this discipline, since it claims to be the best MMX performer. In 3D graphics the Pentium Pro shows its muscles although it’s the only CPU without MMX. Video and audio are best performed by the Pentium MMX which leaves only a very small lead in image processing to give the PPRO the slightly faster overall result.

I can also hardly believe the Monster Truck Madness results. Here the Pentium MMX is clearly the leader.

Finally the Pentium II couldn’t convince us even here, hence again NO POINTS !!

What’s the Beef With Intel’s New Pentium II Then?

Well, the beef with the Pentium II is that it seems to suffer from BSE (bovine spongiform encephelephy a.k.a. Mad Cow Disease), although I doubt that any British cattle was involved. Although BSE infected products shouldn’t be imported, I’m pretty sure we’ll also see the Pentium II here in Europe soon after the 3rd of May when it is finally released. However, since I wouldn’t eat BSE infected beef, I wouldn’t be interested in risking an infection of my computer with this CPU either.

The Pentium II has a good reason why it shouldn’t be called ‘Klamath’ any longer. ‘Klamath’ always sounded quite mysterious and had us thinking that this new CPU would open up new performance dimensions for us. Now it seems obvious that the only new dimensions being opened are new marketing ideas by Intel to increase their profits. It is indeed not much faster than even a Pentium MMX, so why call the child Pentium II? I mean if Intel wanted to be more humorous, they might have called it the Pentium 2 1/2, following the good old Zucker brothers. The next CPU would then be the Pentium 3 1/3 and we would know all what to expect of this one.

To get serious again, let me express my deep disappointment about this not even released new Intel CPU. If this shall be the reason for the Pentium Pro to die I can only laugh.

Mr. *** told me he was ordering his Pentium Pro 200 after he tested the Pentium II. I’ve already got one, but I’ve ordered the next one as well. Even if Intel should increase the clock speed of this CPU soon, everybody will know that the Pentium Pro is the better CPU. Why improve the 16 bit performance of a new CPU but decrease the 32 bit performance? Sixteen bit software is slowly disappearing from the market and today’s power user tries to avoid 16 bit software like the plague anyway. For former Pentium users there’s hardly any attractiveness in the Pentium II either. The Windows 95 performance is hardly any better and in some cases even worse than the cheaper Pentium Pro or Pentium MMX. Windows NT users would be the last ones to be interested in the Pentium II, there is just no reason at all to swap the Pentium Pro for a Pentium II.

The future doesn’t look too great for Intel this time. Intel is just trying too hard to make money. The ‘slot one’ would have been a nice idea to get Intel’s competitors out of business, since this slot is licensed by Intel. However the CPU for this slot should be worth getting in the first place. Intel is trying to drop the Pentium market by not producing any new and advanced Pentium chipsets after the TX, so that you automatically have to change to the Pentium II if you want ECC, SDRAM, RDRAM and AGP. The Pentium Pro could certainly be produced for a 233, 266 or 300 MHz clock speed and it still would be a great CPU for lots of applications, but it looks as if it never will. Intel tries it’s best to force us in one direction, but it hasn’t planned it well enough I think.

The biggest fear to Intel is called AMD. AMD’s new K6 is said to be considerably faster than the Pentium II (‘Klamath’) and it will be released one month earlier (April 3, 1997). But if this wasn’t shocking enough for Intel, AMD is also planning to produce it’s own chipset. This could be the solution for the future of the good old Socket 7 boards. The K6 can be dropped into the Socket 7, Socket 7 is NOT licensed by Intel and if Intel doesn’t produce any high performance chipsets, why shouldn’t AMD take it’s place and produce high performance chipsets for it’s high performance CPU. This would leave Intel completely in the rain and who of us would feel sorry for Intel, who would?

March 7, 1997

The Intel Pentium II was obviously meant to get the buyers into the direction of Slot One Boards, so that the field is already clear for the Deschutes, which is planned to arrive at the end of this year. The Deschutes will run at 300 MHz to start with and it will have a bus speed of 100 MHz, most likely to be achieved via RDRAM. I’m not quite sure if it will include the MMX2 technology as well. Anyhow the question should be asked, “why didn’t Intel skip the Pentium II in the first place?” The only proper way of marketing this chip will hopefully be to offer it at the same or even lower price than the Pentium Pro with 256 kB L2 cache. However Intel will certainly NOT do that, unless we show them our lack of interest in this chip. That’s what Intel hates about this article …

The latest rumor says that Intel WILL produce a Pentium Pro Overdrive with MMX technology! If this chip should have all the enhancements of the Pentium II, like 16 kB data and instruction cache and segment register caches, it will easily outperform the Pentium II even at lower clock speed. However there can hardly be an interest for Intel, since the Pentium Pro fit’s in Socket 8, which Intel is planning to abandon soon. WE have to make clear to Intel, that THIS is what we want. In this case Intel will have to do something about it.

If Intel SHOULD produce this Pentium Pro Overdrive with MMX, I would like to ask why they had to produce the Pentium II at all?? I do understand that the internal L2 cache is very difficult to get running at clock speeds of more than 233 MHz, so that Intel had to do something like getting it out of the chip, however that is exactly what the Deschutes will be like, so what is the Pentium II for ??? It’s simply introducing a new standard (Slot One) to get the competitors out of business and binding us even closer to Intel. This is a very very questionable moral and we should hope that this plan won’t work out !!!