Thursday, February 26, 2009

AMD - Athlon 64 FX-62 and Socket AM2 review

With the launch of Athlon 64 FX-62, AMD has also rolled out its new AM2 platform. This is a move from Socket 939 and Socket 754 to a new processor socket which has 940 pins. That number may sound familiar, but this isn't the same 940-pin layout that is used by the Opteron server processor, hence the name AM2 rather than a number.

AMD is changing its entire range of desktop processors over to AM2, from the highest Athlon 64 X2 to the lowest Sempron. The reason for the change is that AMD has decided that the time is right to shift from DDR system memory to DDR2, which is the same type of memory that Intel started to use with the LGA775 version of Pentium 4.

At that time, DDR2 was relatively slow and had horrendous latency (lag) but Intel was determined to pursue clock speeds that went beyond 4GHz so it needed memory that could provide adequate bandwidth. AMD is in a different position as it has raised clock speeds quite slowly from the initial 1.6GHz of the first Opteron to 2.6GHz with FX-60, and it's only now, with the 2.8GHz of FX-62, that it feels the need for DDR2. Well, that and the fact that 800MHz/PC2-6400 DDR2 is now fast enough to offset the latency problem.

You need to make sure that you choose memory that is fast enough to support your new AM2 processor, so here is a short list of recommended configurations:

AM2 Athlon 64 FX-62 with DDR2-800/PC2-6400 or DDR2-1066/PC2-8500
AM2 Athlon 64 X2 with DDR2-667/PC2-5300 or DDR2-800/PC2-6400
AM2 Athlon 64 and Sempron with DDR2-533/PC2-4200 or DDR2-667/PC2-5300

The other physical change is that the AM2 heatsink frame mounts through four holes on the motherboard, compared to the two holes used by Socket 754 and 939, but ironically the same as the Socket A Athlon circa 2001. The AM2 heatsink attaches to the frame with two clips, rather than the six clips used on the earlier version, and while this looks like a backward step we doubt that it will cause any problems.

Athlon 64 has the memory controller integrated within the processor rather than the motherboard chipset, so there was no need for any dramatic change to the new wave of motherboards apart from a change in processor socket and the memory slots. Indeed, ATi's Radeon Xpress 3200 chipset supports both the old and new Athlon 64, but Nvidia has decided to roll out a new family of chipsets for AM2 called Nforce 500.

There are currently four members of the family with the fully-featured Nforce 590 SLI at the top of the tree, Nforce 570 SLI in the mid-range, Nforce 570 below that and Nforce 550 so far down the pecking order that you'd be better off with Nforce 4, if you were given the option.

The 590 SLI has a pair of graphics slots, each with 16 PCI Express lanes, just like the Nforce4 32 chipset. In total 590 SLI supports 46 lanes of PCI Express. In addition it has LinkBoost which will automatically overclock the graphics buses when you plug in 'compatible' graphics cards, which currently means the GeForce 7900GTX.

You also get a pair of Gigabit LAN ports which can be combined with DualNet to give the equivalent of a 2Gbps connection, while FirstPacket prioritises your Internet traffic so Counter Strike doesn't suddenly fall foul of Windows Update or some other horror.

This is a good idea, but we find the biggest problem with Windows in respect of Internet traffic is that an application such as e-mail or your firewall will grab the Windows focus and present a pop-up that has to be dealt with. If you're gaming in full-screen mode, the pop-up can either kill your game or it can remain invisible behind the game yet still demand attention.

On the subject of firewalls, Nvidia has dropped the hopeless ActiveArmor firewall that it introduced with Nforce4. And every member of Nforce 500 supports Intel's Azalia HD audio.

Nforce 570 SLI supports 28 lanes of PCI Express with x16 for a single graphics card or dual x8 for each graphics card in SLI, just like Nforce4 SLI. It doesn't support LinkBoost but it does have FirstPacket and DualNet. The Nforce 550 doesn't support any of the new technologies, which effectively makes it an Nforce4 with support for AM2 processors.

So, what is the upshot of the move from Socket 939 to AM2? Well, naff all really.
The previous king of the performance charts was the Athlon 64 FX-60, which uses Socket 939 and runs at 2.6GHz on dual channel DDR memory. The new FX-62 runs at 2.8GHz and has exactly the pro rata performance increase that you would expect from the extra 200MHz, which means that the new Socket, new chipset and the change to DDR2 memory have precisely zero effect.

That's not to say that Nforce 570 SLI is a failure, as it has enormous potential in a high-end gaming PC with a pair of GeForce 7900GTX graphics cards, provided you have the necessary £3,000.

Intel - Core 2 Duo E6700 review

In June 2003 Intel released the 3.2GHz Northwood Pentium 4 and after that it entered a black period with the Prescott core which failed miserably to produce decent clock speeds despite a move to a 90nm fabrication process.

To add to Intel's woes, Prescott consumed huge amounts of power and therefore shed enormous amounts of heat. In short, Prescott wasn't a good processor so Intel took the bold step of scrapping the NetBurst architecture, including Prescott's 65nm Tejas successor, and instead returned to the drawing board.

This gave AMD two years of grace, in which time its Athlon 64 and Opteron processors have ruled the roost. But now Intel is back and it means business. The new desktop processor that launches this month is Core 2 Duo. This is the second version of Intel's notebook Core processor, while the 'Duo' means it is dual core, so in time we shall doubtless see Core 3 Trio and then Core 4 Quadro, or perhaps that should be Core 4 Quattro.

Core 2 Duo takes Intel's desktop processors in a new direction by putting the emphasis on efficiency rather than clock speed, so the new processors run on a Quad-pumped 266MHz Front Side Bus which is the equivalent of 1,066MHz.

However, the actual clock speeds are relatively low. The E6300 runs at 1.86GHz and costs £153, the E6400 is 2.13GHz and costs £182, the E6600 gives you 2.40GHz for £253 and the top-of-the-line E6700 has a clock speed of 2.67GHz and is on sale at £411.

In truth there's one more member of the family as the X6800 will be released about a month after the E series processors, but as this 2.93GHz Extreme processor will cost about £800 it's safe to say that sales will be low, even if its clock multiplier is unlocked and thus offers the prospect of some serious overclocking.

Intel Core 2 Duo has a much shorter pipeline length than the NetBurst Pentium 4 processors and it also uses the L2 cache as a shared pool, instead of dividing it into two even chunks with half reserved for each core. E6300 and E6400 have 2MB of L2 while the faster processors have 4MB of cache.

We can waffle on all day about the technical features but what counts is how the new processor performs. Recently this reviewer ran a group test of AM2 motherboards and in each case the AMD Athlon 64 FX-62 processor encoded a 350MB DivX movie file to DVD format in about 13 minutes. This test almost ignores the motherboard, chipset, memory and hard drive and puts the emphasis on the processor. The fastest AM2 board managed it in 13 minutes dead while the slowest came in at 13 minutes 22 seconds. In the bad old days before dual core processors, an Athlon 64 3800+ would take about half an hour.

By contrast the Core 2 Duo E6700 took 9 minutes 52 seconds and it is worth noting that the E6700 runs at 2.67GHz while the FX-62 has a clock speed of 2.8GHz, so the Core 2 Duo is much more powerful even at a nominally slower clock speed. And throughout the test the processor heatsink remained cool to the touch.

We also ran PCMark05 and the Core 2 Duo scored very well in every section of the benchmark, so make no mistake about it: Core2 Duo is a fabulous processor. But of course you need more than a bare chip inside your PC and this is where things get a bit confusing.

Intel supports Core 2 Duo with the current i975X chipset which it launched in December 2005 and, as Core 2 Duo uses the same LGA775 socket as the later models of Pentium 4, you might hope that this provides a direct upgrade path.

Think again.

Intel's Press kit includes a new revision of its D975XBX motherboard, however our year-old version of the same board wouldn't boot with Core 2 Duo installed even though we had upgraded the BIOS to the latest version. We understand that the new D975XBX board has significant revisions to the power regulation hardware, so if you want a Core 2 Duo you'll need a new motherboard in which case you may as well opt for the latest 965P chipset which launches alongside Core 2 Duo.

This chipset supports the fastest DDR2 memory and 1,066MHz FSB and is paired with the new ICH8 Southbridge which supports six SATA ports and HD audio. Unfortunately it doesn't support IDE, so most motherboards will have an add-in controller to allow you to connect your optical drive.

The ominous thing is that you can't connect a pair of Nvidia graphics cards in SLI on an Intel chipset motherboard as the graphics drivers require a suitable Nvidia chipset, so for the moment you are limited to a single graphics card or a pair of ATi cards in CrossFire. Gamers will, therefore, probably want to avoid the Intel chipsets.

Happily, Nvidia is a launch partner with the new Intel processor and it will unveil versions of the Nforce 500 chipsets that we saw with the AMD AM2 platform, and very good they are too. We'll reserve judgement until we've seen the new silicon but the Intel versions of Nforce4 ran incredibly hot which was probably related to the additional memory controller that Nvidia had to integrate in the Northbridge. AMD, of course, includes the memory controller in the CPU core while an Intel processor leaves the job to the chipset.

Nforce 500 is superb on the AMD platform and provided Nvidia's done the job correctly we expect that gamers will migrate to the Nforce 590 SLI in their droves. Still, gamers are only part of the market, so what about the rest of us?

We tested our E6700 on an Asus P5B Deluxe with P965 and ICH8R chipset, 2GB of Corsair XMS 8500 memory and a WD Raptor 150GB hard drive. The motherboard employs passive cooling throughout and during our performance testing we ran a noisy Sapphire X1900 XTX graphics card to generate some impressive results.

Once we were done we swapped the Sapphire for a passively cooled Asus EN7600GS graphics card and plugged in a fan controller on the CPU heatsink. We turned the controller down to barely audible levels and measured the heatsink temperature at 35 degrees while the graphics card touched 51 degrees during testing. Performance was adequate for all but the most demanding gaming and the noise level of the PC was very close to silent.

Intel - Core 2 Extreme QX6700 review

Intel is on a roll after the launch of Core 2 Duo E6700 in July 2006 and here we are, a mere four months later, with the launch of the quad core Core 2 Extreme QX6700 which was codename Kentsfield during development.

No doubt when Intel releases non-Extreme versions of this processor they will be called Core 2 Quadro or Quattro or something to reflect the four cores, provided it can find a name that hasn't been snapped up by Nvidia for professional graphics cards or Audi for four wheel drive cars.

In essence Intel has shoehorned a pair of Core 2 Duo processors on to a single LGA775 die, so the quad core runs on the same 1,066MHz Front Side Bus as Core 2 Duo and is fabricated on a 65nm process. There is 4MB of L2 cache for each pair of cores, so that's a total of 8MB of cache, and the core speed is similar to Core 2 Duo.

Core 2 Duo E6700 runs at 2.66GHz and has a TDP (Thermal Design Power) of 65W while the Core 2 Duo Extreme X6800 runs at 2.963GHz and has a TDP of 75W. By contrast the quad core Core 2 Extreme QX6700 runs at 2.66GHz and has a TDP of 130W so it truly is a pair of E6700 CPUs in a single processor socket. Let's not lose sight of the fact that the final versions of dual core Pentium 4 had a similar heat profile, so the technology to keep the processor cool is well established.

The Intel Press kit consisted of a QX6700 processor, a heatsink and a D975XBX2 motherboard with a Beta BIOS. Although the 975X chipset supports both Core 2 Duo and Kentsfield, it isn't necessarily the case that every 975X motherboard will support Kentsfield, so you need to check that your motherboard is 'validated for quad core'.

We understand that the differences between a 'good' motherboard and a 'bad' one come down to power regulation hardware. We laid the D975XBX2 next to a D975XBX and were unable to see any differences, but were told that the new board supports DDR2-800 memory and has enhanced audio control. Once we'd finished testing we played mix and match by plugging the quad core into the old D975XBX and it performed perfectly.

The move from a single core processor to dual core was like the difference between night and day, as you suddenly find that burning a CD or encoding MP3s doesn't make your whole PC freeze solid.

The move to quad core is far less dramatic as there is a limit to the number of applications that you can run simultaneously, but even so there's Windows in the background, your e-mail agent, anti-virus, anti-spyware, the music you're playing, your Internet browser, Word and Excel. By contrast an intensive 3D game is unlikely to use all of the abilities of the processor as very few games are threaded for multi-processor hardware.

We ran POV-Ray rendering benchmark on the Core 2 Extreme QX6700 as the 3.7 Beta has the facility to run on a single core or on all available cores. On a single core the test took 10 minutes 4 seconds, which is fairly swift, but when we switched to all four cores the test flashed past in 2 minutes 29 seconds.

Clearly the quad core hardware works, and when we ran PCMark05 back-to-back with the Core 2 Duo E6700 (same clock speed, half the cores) we found that the quad core got 8,150 marks and the dual core scored 6,879 marks overall, while the CPU elements of the test also favoured the quad core at 8,433 marks compared to 6,715 marks.

To our mind that accurately reflects the fact that most of us have no need for a quad core processor most of the time, but when you start to make your PC work for its living the extra cores pay dividends.
Intel - Core 2 Extreme QX6700 features - Verdict

In a few years' time we'll be amazed that there was an era when people had to make do with fewer than eight processor cores. The Intel Core 2 Extreme QX6700 is a significant step along the way to processing Nirvana and, although it costs a small fortune, we're very happy that its time has come.

Intel - Core 2 Extreme QX9650 review

Intel is releasing information about its next-generation Penryn Core 2 processors in carefully controlled stages. Penryn is the code name for the move from a 65nm process to 45nm, which dramatically reduces the size of the processor core. This reduces the cost of production and also frees up space on the core, so Intel is able to raise the quantity of L2 cache from 4MB to 6MB for each dual core Wolfdale package.

Penryn uses the same LGA775 package as Kentsfield and also shares the same layout, so a quad core processor uses two dual core chips, each with their own L2 cache. In the case of a quad core Yorkfield Penryn the amount of cache increases from 8MB to 12MB.

The other new feature with Penryn is the SSE4 instruction set. If you're running software that supports SSE3 or earlier then you shouldn't expect Penryn to show an advantage over Kentsfield. On the other hand, software such as the latest version of the DivX encoder that does support SSE4 should show Penryn in its best colours.

Intel told us about the architecture and fabrication process of Penryn early in 2007 and it has drip-fed us with information as part of its tick-tock process. In 2007 (a tick year) we'll see Penryn replacing Kentsfield with the new fabrication process on the same 1,333MHz FSB at similar speeds to Kentsfield. In 2008 - officially designated a tock year - Penryn will move to a 1,600MHz FSB and speeds will ramp up towards 4GHz.

We now have a sample of the 3.00GHz QX9650 quad-core Penryn which is directly comparable with the QX6850, so we can report on the performance of Penryn but we don't know anything about the pricing of the new processor.

Well, strictly speaking that's not true, as the QX9650 will be priced at $999 in quantities of 1,000 but that's always the case with the fastest CPU in any of Intel's ranges of desktop processors. Intel will tell us about pricing of the rest of the range in a week or two as the launch of QX9650 is presumably intended to spoil AMD's imminent launch of Phenom, but we can make some informed guesses.

The quad-core Q9550 will run at 2.83GHz with a price about half the QX9650, say £349. There will probably be a 2.66GHz Q9450 priced around the £199 mark and maybe a Q9300 that runs at 2.5GHz which will be somewhat cheaper.

Dual core models will be more relevant to the man in the street so the 3.16GHz E8500 may well be the gaming processor of choice for less than £200. We expect the 3.0GHz E8400 to cost close to £100 and then there will be cheaper, slower models such as a 2.83GHz E8300 and a 2.66GHz E8200.

But that's all guesswork.

We compared the QX9650 with a QX6850 which both run at 3.00GHz on a 1,333MHz FSB using an Asus Maximus Formula SE motherboard with X38 chipset and 2GB of fast DDR2 memory on Windows XP SP2.

In PCMark05 there was near-identical performance from both processors so we don't expect that Penryn is going to cause a revolution, however it showed a small advantage in video recoding with Nero 8 and a decent seven percent saving in time when we used the SSE4-enabled DivX 6.7.