I don’t think that you will consider our recent reviews of quad-core AMD Phenom processors optimistic in any way. Unfortunately, the micro-architectural improvements didn’t help AMD achieve any parity with the competitor’s solutions. That is why the AMD Phenom processors that have been in the market until this day were defeated by Intel Core 2 Quad in terms of performance as well as heat dissipation. Moreover, AMD Phenom didn’t hit competitive working frequencies, too. However, the most frustrating drawback of the new quad-core AMD processors was the so-called “TLB-bug”, which software fix affected the systems performance quite noticeably. And even though this bug didn’t really show that often in desktop platforms, it still had a negative effect on the overall Phenom image. Especially, since it did flowing in the server market forcing AMD to even temporarily stop shipping their quad-core Opteron processors aka Barcelona.
That is why all the engineering effort was thrown to fix the notorious TBL-bus on the hardware level as soon as possible. And the resolution didn’t keep us waiting for too long. Today AMD officially launched Phenom processors based on new B3 stepping that is free from this TLB issue. The core doesn’t have any other improvements as of yet, but nevertheless, this announcement allows AMD to improve the consumer attractiveness of their solutions. Besides, the clock speeds get a little higher and the prices drop a little lower. As a result, refreshed Phenom processors now look much better and more attractive than before.
The new Phenom processor family on B3 stepping includes four models: 9550, 9650, 9750 and 9850 Black Edition. The youngest models replace Phenom 9500 and Phenom 9600, while the two top models push the clock frequency to 2.4 and 2.5GHz respectively. Note that the last two digits – “50” – in the CPU marking stand for the new processor stepping that doesn’t have the TLB-bug anymore. Nevertheless, new Phenom processors shouldn’t be any different from practical standpoint from the old ones working at the same clock frequency and with software TLB fix disabled. The advantage of the new processor stepping is mainly no need to use the patch that aggravates the performance. Especially since its enabling or disabling may require certain effort and qualifications. While most mainboard manufacturers made it possible to activate or deactivate the patch from their BIOS Setup, Windows Vista SP1 that also has a fix for this bug doesn’t offer this flexibility and enables bus fix automatically, no matter what the user actually wants. In this case the only way for the owners of processors on old B2 stepping to avoid performance drop even at the expense of some system stability is to use special utilities such as AMD Overdrive, for instance.
Besides, AMD also officially announced their triple-core processors known as Toliman. At this time they will only be distributed among AMD OEM partners and will not get into retail, so we will have to postpone our review of these CPUs for a little while. Especially since at first they will still be using B2 processor stepping. However, we had to mention triple-core Phenom processors here, because AMD has once again changed their CPU marking strategy a little bit. Quad-core Phenom CPUs will now be called Phenom X4, triple-core – Phenom X3 and dual-core processors will remain Athlon X2.