AMD A8-3870K Black Edition & Hybrid Crossfire Review Page: 1

AMD A8-3870K Black Edition Review 


Things have been tough on AMD in the CPU side of the business lately. Whilst the Radeon arm has been pumping out some extraordinarily high performing graphics cards, the CPUs have been lackluster. Indeed the much-anticipated Bulldozer processors were nothing short of disappointing. In almost ever sector of the market from the very high-end down to the budget sector, Intel have been dominating the performance aspect.

Today we're taking a look at the A8-3870K from AMD, a CPU that is definitely aimed squarely at the budget audience, and comes with a built in HD6650D iGPU to make low-stress gaming on a CPU a possible reality.

So with a price of a mere £100, an unlocked multiplier, and a relatively good integrated graphics option, does the value portion of the AMD product range provide something good, or is it more of the same?

Technical Specifications

Based around the 32nm process on the FM1 socket, the 3870K is a 3GHz Quad Core CPU, supporting 1866MHz DDR3 and with a low (for AMD) TDP of 100W. This latest range has a wealth of models available, but thanks to the aggressive pricing we're looking at the highest end model.

CPU Model:3870K Black Edition
CPU Features:AMD Virtualization (AMD-V)
Enhanced 3DNow!
Core:Quad Core
Core Name:Lynx
Core Size:32 nm
Clock Speed:3.0 GHz
Turbo Speed:N/A
Graphics Chipset:AMD Radeon HD 6550D
Graphics Cores:400
Graphics Clock:600 MHz
Max. Memory Speed:DDR3 - 1866
L2 Cache (Total):1MB x 4
Voltage:0.9125 - 1.4125 (V)


AMD A8-3870K Black Edition & Hybrid Crossfire Review Page: 2

AMD A8-3870K Black Edition Review

Test Setup

AMD A8-3870K
HD6670 (Hybrid Crossfire)
Asus AM1 F1A75-M Pro
8GB Corsair Vengeance
Corsair H80
Corsair AX650W
Windows 7 x64


As always we start by seeking the highest multiplier available, which for the A8-3870K is x38. 

AMD A8-3870K Black Edition Review  

The highest Bus Speed we were able to obtain is 160MHz.

AMD A8-3870K Black Edition Review  

So in total we managed to overclock the A8-3870K to 3.6GHz, a nice 600MHz increase over the stock chip. At these speeds the CPU topped out at 68°C, which is not too bad at all.

Of course the CPU isn't the only thing that is available for overclocking, or indeed the only part we need to take account of when ensuring we don't become thermally limited, and the integrated HD6550D GPU can be pushed from it's default setting of 800MHz up to 960MHz. This is the speed that we'll be running our overclocked tests at, including the hybrid Crossfire ones.

AMD A8-3870K Black Edition Review   AMD A8-3870K Black Edition Review  

AMD A8-3870K Black Edition & Hybrid Crossfire Review Page: 3

AMD A8-3870K Black Edition Review


Performance wise the A8-3870K is about where we'd expect an AMD CPU of this price to be. Of course it's dominated in the graph by everything else, but that's not really the point. In the Memory tests it slots in neatly between the 1095T and FX8150, although AMD are still nowhere near anything Intel have produced, and improving this area should definitely be a priority for the next generation of AMD CPUs.




AMD A8-3870K Black Edition & Hybrid Crossfire Review Page: 4

AMD A8-3870K Black Edition Review

SiSoft Sandra

Despite a 600MHz overclock we don't really see a major improvement in Sandra. Indeed even the 1095T is a country mile ahead. Probably the most surprising result is the Int x16 test in the Processor MultiMedia, where the A8-3870K is the first CPU we can recall ever giving a lower score than the x8 test.

Processor Arithmetic


Processor MultiMedia


AMD A8-3870K Black Edition & Hybrid Crossfire Review Page: 5

AMD A8-3870K Black Edition Review


Firstly it's worth pointing out that from the FX8150 down the OpenGL results were obtained on a GTX570, and from the rest on a HD7970. Even still the HD6550D gets its first test and performs much better than we'd anticipated. Certainly it is by no means disgraced. The CPU scores aren't bad either for a straight Quad Core, especially when we see how average the FX8150 results are.


POV-Ray has two major areas of comparison. The absolute speed, and the rendering speed available from each core. As we can see the overall performance isn't too bad when compared to some much more expensive hardware, and the per CPU score is right in the ballpark.


AMD A8-3870K Black Edition & Hybrid Crossfire Review Page: 6

AMD A8-3870K Black Edition Review

PC Mark Vantage

Again the A8-3870K is surprisingly capable when compared to the 8 Core FX8150. Of course the Intel stuff is streets ahead, but the Llano handles itself well. Especially impressive is the iGPU in the gaming test, considering how little extra performance we gain from the Hybrid-Crossfire.


PC Mark 7

In the more up-to-date PC Mark 7 the A8 scales nicely and shows that for a budget desktop environment it's more than capable of punching above its weight.

AMD A8-3870K Black Edition & Hybrid Crossfire Review Page: 7

AMD A8-3870K Black Edition Review

3D Mark Vantage

A gaming behemoth it certainly isn't, although integrated GPUs have never been benchmark kings. It does throw up a pretty eye-opening result when we compare it to the current Intel option, the HD4000. The HD6550D is a much better performer, especially with the overclock. All previous results were tested with a GTX570 GPU on each of the seperate CPU results.


3D Mark 11

The results are, if anything, even more impressive in 3D Mark 11. It's a mile ahead of the Intel offering and should provide a reasonable level of gaming performance in non-demanding titles.


AMD A8-3870K Black Edition & Hybrid Crossfire Review Page: 8

AMD A8-3870K Black Edition Review

Alien vs Predator

Not exactly a playable frame-rate, but we hope that nobody would purchase this with the intent of running at such extreme resolutions and detail levels that we see from AvP. Adding a £60 graphics card makes a world of difference of course, but it also shows how well the Hybrid-Crossfire works.

Unigine 0xAA

Unquestionably the HD6550D in the A8-3870K is a handy performer for an integrated solution, running the HD4000 close and with the bargain-basement Crossfire arrangement it romps ahead.


AMD A8-3870K Black Edition & Hybrid Crossfire Review Page: 9

AMD A8-3870K Black Edition Review


It's very easy to get bogged down in the high-end hardware, the cream of the crop, and forget what a joy there is to be had from something that is almost proudly cheap and cheerful. AMD have nearly always been the providers of exceptionally good performing CPUs at a much more affordable price-point than Intel. Of course things rapidly changed a little while ago with the introduction of the LGA115x socket CPUs from Intel, and the relatively disappointing performance of the Phenom IIs, and latterly the FX8150. When you laud your latest CPU as the flagship disappointment is almost inevitable.

The Llano A8-3870K is most certainly not lauded as an Octocore monster. It's a quiet little 3GHz Quad-Core with a decent integrated graphics solution, and it's all the better for it.

Sure the CPU performance isn't outstanding when compared to the Intel options. Even the i5-2405S, the 3GHz Quad Intel equivalent, outperforms it fairly well. But compared to the performance we've been seeing from AMD of late it's exactly where you'd hope it to be. The unlocking of the multiplier helps the overclocking too, and by tweaking both the CPU clockspeed and the HD6550D GPU speed, some decent performance is there to be had.

It's all about understanding the performance available and tailoring your expectations to suit. The Unigine/AvP and Extreme 3D Mark tests don't set the world on fire, but if you were playing at a more realistic 720P resolution (3D Mark P score territory) the 3870K has a surprising amount of power available. Certainly more than we've seen from the latest HD4000 Intel option.

In fact the only real dilemma comes from AMD themselves. Such is the extremely tight gap between the price of this CPU and the price of their full-fat FX8150 that it's difficult to see why you'd choose this model over any others. If you just want the CPU side of things to be decent, then the FX6100 has six 3.3GHz cores for the same money. Or for about twenty pounds less you can retain your AM3 motherboard and grab a Phenom II X4 965. The other limitation is the small selection of GPUs that support the Hybrid-Crossfire. They're all underpowered and overpriced and there are much more powerful options available for around the same money. So although Hybrid-Crossfire is an option, it's not one that makes sense because if you're going to have to buy a GPU you might as well get a better GPU and a better pure CPU to go alongside it, even if you insist on sticking with AMD.

So this has a very small target audience of people who just want a CPU that is a decent performer that will cope with most home tasks without breaking a sweat and has a decent integrated graphics chip for some light gaming at medium resolutions. To these people it's definitely great value for money.


Thanks to AMD for providing the A8-3870K for review. Discuss in the OC3D forums.