AMD Phenom X3 8750

AMD's Phenom X3 8750 triple-core processor

Manufacturer: AMD
UK Price (as reviewed): £128.08 (inc. VAT)
US Price (as reviewed: $195.00 (ex. Tax)

Today AMD is releasing its first triple-core processors to the retail market after initially announcing them on the eve of IDF Fall 2007 in an attempt to steal away some of the limelight from Intel’s twice yearly shindig.

Don’t be fooled though, these aren’t the first ever triple-core processors AMD has released, we’d spotted several Mesh machines using triple-core Phenom 8400 and 8600 processors long before AMD officially announced them late last month.

Because of the release timeframe, they were of course based on the older B2 stepping but, unlike today’s launch, those processors were limited to system builders only. This was probably due to the fact that the B2 stepping chips weren’t exactly renowned for overclocking and shipping with relatively cheap systems would be a way to shift the old stock as quick as possible.

In fact, saying that the B2 Phenoms were poor overclockers is probably an understatement because, of the two Phenom 9600 Black Edition processors we received, neither managed to remain stable above their stock clock speeds on a consistent basis and the whole overclocking malarkey was a complete non-event. But that’s not all that was wrong with Phenom, because there was the infamous but now largely forgotten Translation Look-aside Buffer erratum that sat right at the heart of the bad press AMD’s first native quad-core processors initially received.

AMD feels that this was largely over-exaggerated, but a lot of that was down to its own doing in our opinion. And to some extent AMD agrees because it has said that it wished it had handled the situation a little differently in hindsight.

The problem, though, was that when the company disclosed the bug to the press in Warsaw, it didn’t know enough about it. In that respect, hindsight is a wonderful phenomenon and AMD believes that if it had understood the problem in a bit more detail, it could have presented a compelling enough case for the press to essentially not worry about it ever affecting consumers considering purchasing the products.

Indeed, we feel it was the lack of confidence surrounding the issue that came out of AMD was ultimately what hampered the chip maker’s launch. But let’s forget about that for now because things have changed with the B3-stepping – not only is the TLB bug fixed, but the 9x50 processors we’ve seen so far have also overclocked fairly well too.

A Core “For Free”

AMD is announcing a total of three new triple-core processors today, the X3 8750, X3 8650 and X3 8450 – they’re clocked at 2.4GHz, 2.3GHz and 2.1GHz respectively and all use the B3 revision silicon. What’s interesting is that CPU-Z recognises the Phenom X3 8750 as a 65nm ‘Toliman’ core, which confirms the rumours we reported last December and, what’s more, AMD’s documentation confirms that this is nothing more than a 65nm ‘Agena’ die with one core disabled.

Both chips have an approximate transistor count of 450 million transistors packed into a 285mm² die size. Like the equivalently clocked Phenom X4 processors, all of the Phenom X3 chips feature a 1.8GHz north bridge and memory controller clock along with a 16-bit/16-bit full duplex HyperTransport 3.0 link running at up to 3.6GHz.

Each core features its own 64KB L1 data and 64KB L1 instruction caches, along with a 512KB L2 cache, meaning a total of 384KB of L1 cache and 1.5MB of L2 cache. This is obviously slightly less than the Phenom X4 processors, but that’s because there are fewer cores – the shared L3 cache remains the same at 2MB and it runs at the same speed as the north bridge (1.8GHz).

Pricing for the processors is where things get interesting, because AMD is aiming to hit price points below all of the current Phenom X4 processors. According to AMD’s projections, the Phenom X3 8750 will be priced at $189 USD per chip when purchased in 1,000-unit quantities. Meanwhile, the 8650 and 8450 will hit $159 USD and $139 USD per processor respectively, in the same 1,000-unit amounts.

This puts them up against Intel’s faster dual-core E6850 (3.00GHz, 4MB L2 cache, 65nm), E8300 (2.83GHz, 6MB L2 cache, 45nm) and E7200 (2.53GHz, 3MB L2 cache, 45nm) processors which should make things quite interesting because AMD is entering into a core war that it said it never planned to enter. Indeed, the company believes that what it is offering with the triple-core processors is comparable performance to existing mid-range dual-core Athlon 64 processors and an extra core “for free”. That’s a fairly loose quote though because according to AMD’s expected pricing, the extra core isn’t quite as free as it sounds.

After spending some time talking with AMD’s representatives, the company believes that the Phenom X3 processors are an upgrade option for those that already have a socket AM2 platform. This is because all of the Phenom X3 processors are rated with a maximum TDP of 95W, meaning that motherboard support should be pretty pervasive, unlike the 125W processors that aren’t supported by many of the cheaper boards.

Without further ado, let’s get on and find out how the Phenom X3 8750 processor shapes up...