[Manuel Calavera]

Hands-on Review & Overclocking Athlon X4 845: Cheap Carrizo Without IGP

Vidi se da ima bolji IPC:

Can be seen, at the same clock in both benchmarks, the Athlon X4 845 excels between 3.5 - 11% of X4 860K depends what benchmarks and scenarios run. Roughly, this corresponds to the estimated core AMD estimates that the excavator will increase 4-15% depending on the type of workload it.

Ali ima čudne gaming rezultate (vjerojatno zbog manjeg L2 cache). Oni su testirali samo GTA, ali ovaj neki youtuber je više

Efikasnost je poprilično bolja od steamrollera, a imaju i zanimljiv test novog coolera u toj recenziji.

Inače tko ne zna, taj carizzo navodno nije ni planiran za izdavanje na desktop (fm2+), jer je navodno najefikasniji do TDP 35w. Onda je slučajno uletio taj 845, ali je evidentno da je to prenamjenjeni mobilni procesor. Stariji tekst:

The goal of Excavator, as we were told at the time, was to develop a series of big steps into improving the efficiency of the base Bulldozer microarchitecture through high density libraries, better metal stacks in production, more on-chip analysis to save power, more power planes to regulate those chances and everything in-between. We were told we wouldn’t see the Excavator core on the desktop in its desktop form because the design focused on the 15W-35W power window, rather than the 45W+ on the desktop.
Fast forward to today and there seems to be a slight reversal here. The new AMD Athlon X4 845 is a pair of Excavator modules in a desktop package, designed to slot right in where the Steamroller design through Kaveri has been sitting for a couple of years. Why the change? And why a single SKU at 65W, way off the 15W-35W range quoted as 'ideal' back at the Tech Day?


One thing that was made perfectly clear in AMD’s briefing on the new Athlon was that this is not a performance part – due to the nature of Excavator the new CPU would be purely an efficiency play, allowing customers to take advantage of the latest architecture in the desktop if they didn’t need the full-fat performance.

With the new Athlon, the fact that there is no graphics part to the FM2+ processor does raise several questions. Is this a new die specifically for the Excavator on desktop, which might run into the tens of millions of dollars to produce, or is it repurposed mobile silicon put into a desktop package. Instinct tells us it’s the latter, perhaps better binned parts to show that the core can do 3.8 GHz at 65W, but at the expense of the integrated graphics, or due to production issues the integrated graphics on die are unusable. One of the interesting things is also the L2 cache situation, because the Excavator modules in Carrizo were designed with 1MB of L2 per module, rather than the 2MB of L2 cache per module in desktop Kaveri. This is somewhat balanced by the larger L1 data cache in Excavator, but because there is no L3 cache either, it has to rely on other Excavator enhancements (better prefetch, wider prefetch windows) in order to bring it up to speed.

The PCIe 3.0 lanes are also at x8, which is another mobile limitation rather than the result of the PCIe root complex being half-disabled.