THE CPU

AMD Ryzen 5_lAvid gaming computers generally use mid to high-end processors. We have both Intel and AMD processors and we have noticed that AMD is far easier to upgrade with than Intel.

We presently have 2 AMD machines. The gaming machine uses a quqd core processor and the server uses a dual core processor. The server uses socket AM3 and the gaming rig is AM3+.

Intel has adopted the AMD idea of using an on-die memory controller. AMD actually spans DDR2 and DDR3 on their processors which means upgrades are comparatively easier. Intel dumped DDR2 support long ago.

AMD and Intel generally provide 140W maximum with their enthusiast processors. More recently AMD has offered 220W processors to compete with Intel’s 150W models. The move to less power hungry processors is increasingly attractive. DX12 and Mantle will result in a lower CPU load which reduces the need for the flagship models.

THE ALU

Inside the CPU is a simple device called the arithmetic logic unit or ALU. It can do addition, multiplication and negation etc.

INSTRUCTION SET

The instruction set on a CPU is actually termed microprogrammed. The ALU is matched with additional logic to perform many functions faster than could be done with external instructions. The users instruction set is the higher level commands that are programmed internally around the ALU. With more functionality being added to the CPU die, the concept of a CPU becomes more abstract. This is driven largely by extremely large scale integration. There is so much room for additional capability so internally the CPU now has a bus of its own to cope with various devices.

The modern gaming PC has long ago moved to 64-bit. AMD simply stretched the registers like Intel did with the 80386 long ago. This allowed backwards compatibility all way to DOS. We have been using an AM3 Phenom II X4 965 BE CPU for our gaming machine. The 965 runs at 3.4 GHz out of the box and its generally fast enough to run any graphics card available. The 6 MB of L3 cache add about 30% more performance compared to the older design with 2 MB. The Phenom II also has a different implementation of Cool & Quiet that changes from individual cores to the CPU generally to deal with the way Windows Vista manages the CPU cores.

The FX-8350 offers a faster clock and more L3 in addition to more cores. Intel has some somewhat faster processors but they are more costly.

Windows has been available in 64-bit since 2003 when Microsoft started selling an OEM CD to enthusiasts. When Vista shipped it offered a choice of 32-bit or 64-bit and continued using the 64-bit visions since. Only extremely old games are rarely a problem with 64-bit Windows.

CPU PERFORMANCE

DDR3 is not significantly faster than DDR2 in the real world. Dynamic RAM has suffered from performance issues for many years.

A lot of games are bottlenecked by the CPU nowadays because a lot of games are designed with consoles in mind. When its ported to the PC they don optimize the engine and a lot of stuff runs on the CPU. For example, the performance in Skyrim scales almost linearly with faster CPUs. SSE and the GPU can provide stellar gains in performance if used properly.

We installed Brink after we upgraded the CPU to the Phenom II 965 to see if it would work any better. Console ports from the Xbox 360 and PS3 are more demanding compared to the older console period.

DDR2

L1 L2 L3 MAIN
Sempron 3400+
Athlon64 X2 4200+ 17,265 MB/s 3,348 MB/s 2,769 MB/s
Phenom II X4 965 BE 55,990 MB/s 15,885 MB/s 9,107 MB/s 3,405 MB/s

Results taken from memtest86+. CPU performance is on our M2N-VM CSM with 2 sticks of memory installed for dual channel operation. We may expand this table if more processors become available.

DDR3

L1 L2 L3 MAIN
Phenom II X4 965 BE 65,433 MB/s 20,574 MB/s 8,869 MB/s 4,641 MB/s

DDR3-1600 is the maximum speed in the JEDEC tables however due to the delay introducing DDR4, Intel added the XMS tables to provide for higher speed operation.

DDR4

L1 L2 L3 MAIN
i7-6700K

DDR4 span 1600 to 3200 MHz. Much higher speeds are found in the market in 2015. DDR4-2133 seems to be the mainstream speed.

Results taken from memtest86+. CPU performance is on our M5A99FX PRO R2.0 with 2 sticks of memory installed for dual channel operation. We may expand this table if more processors become available.

The Xbox One and PS4 both are using 8 GB which is the same as we use now. Graphics cards add to the total memory so with a pair of 896MB cards the total is more like 9984MB of memory. Adding another pair of memory sticks is not likely needed.

CORES

A quad-core CPU running at 3 GHz or faster will be adequate to play Xbox 360 and PS3 period titles without much concern for badly optimized titles.

The Xbox One and PS4 use an 8-core processor with a lower clock speed. Any X8 processor offered to the PC market will be fine.

OVERCLOCKING

We now have a separate page for CPU overclocking. AMD and Intel both have tools for their respective products.

Periodically we see posts of extreme overclock processors. For example in January 2010 somebody used a phase change cooler to get 6.025 GHz out of a Phenom II 955 CPU. Then somebody overclocked a Celeron to an every higher speed. On air, the Phenom II 955 can achieve close to 4 GHz.

Phase change coolers are far more powerful than a water cooler. These units are essentially a mini-refrigerated CPU cooler. The condenser and the pump are usually housed below the main chassis or they may be integrated. In effect you have a refrigerated cooler for your CPU. Recent models we have seen can handle 200W processors.

Even more extreme is the use of liquid nitrogen. This is more or less the same idea as the refrigerated cooler but using liquid nitrogen at -196°C. To make liquid nitrogen requires a 300 atmosphere industrial compressor. The compressed air is fed through a double tubed heat exchanger. Then the compressed air is released though a small jet valve. Boyle’s law cools a gas as it expands and this is how liquid air is made because after a time the temperature will fall enough for drops of liquid air to form. Using a fractionation column is possible to separate liquid oxygen (-183°C) and argon (-186°C) from the nitrogen.

Another technique using a turboexpander can create liquid air products at lower capital cost. Using a twin turbine with one compressor and and expander can create refrigeration.  Turboexpanders are now able to reach cryogenic temperatures.

We should also mention that operating a CPU in such an extreme environment such as using liquid nitrogen severely shortens the service life.

PERFORMANCE

Testing Steam and Origin clients we note that they use excessive amounts of CPU time. There is not reason for them to be in the Windows startup where they gobble up RAM and CPU with a vengeance. Press windows+r and enter msconfig to change startup programs.

The task manager with Windows 7 does not show CPU time by default but its available by adding the column in the processes view. Sorting my CPU time will quickly show what programs are bogging down your system.

Cleaning up your startup will enhance performance significantly. Excess CPU load can have a significant impact on games. It also frees up memory so that more is available for games.

STABILITY

When we used the AMD overdrive tool on our gaming box, we noticed it was not able to tune the clock rate properly. The base clock is 200 MHz and we manually were able to achieve 260 MHz without stability problems. The AMD tool attempted to reach 266 MHz but it was very unstable.

After reducing the RAM speed to the lowest (200 MHz = DDR2-400), we were able to rise the base clock up to 275 MHz and it has tested stable. This means we have achieved 3.025 GHz with the Athlon64 X2 4200+ which is a very good overclock indeed. Obviously the CPU is probably running closer to 90 W TDP at that speed.

Overclocking a CPU will adversely affect the service life. The more aggressive the overclock the shorter the expected service live.

BULLDOZER

We found a graphic for the AMD bulldozer core that will be the central core for Opteron and Phenom FX processors looking forward.

AMD is using a version of the hypertransport between core blocks to scale up to 8 blocks giving 16 cores.
AMD Bulldozer architecture

HOTFIX

Windows XP, Vista and 7 does not recognize all of the cores on the FX line of processors properly.

For users of Windows 8 these hotfixes are not needed as the FX line is now correctly supported.

AMD FX-8150

Here we present the first benchmark of the new AMD FX-8150. The popular Fritz is a chess program has an intrinsic benchmark which is highly regarded in chess forums.

As you can see the new CPU holds up well even against Intel’s most expensive CPU. The new AMD CPU will cost far less which will definitely stir the sector up.

The FX-8150 needs a driver for Windows in order to get reasonable performance. This is due to the architecture that is similar to the hyperthreading found in Intel processors.

WORLD RECORD OVERCLOCK

Seems every few years somebody goes to extremes to overclock their processor. We speculate that the extreme CPU overclock probably shortened the effective life considerably. Semiconductors are not designed to operate at such extremes.

INTEL FIGHTS BACK

 

PHASE CHANGE

Phase change coolers are available but they are not very popular due to the cost and the noise.

ROADMAP

As of January 2012, TSMC is now in volume production for 28 nm and the line likely will be in operation for 3 or 4 years before its obsolete. The 20 nm line is should be in full production by mid 2013 when new video cards are released. TSMC is also working on a 16 nm line for 2014.

AMD and Intel both are slowly moving towards 14nm circa 2015. At this point ultra low power portables that can operate all day will be inexpensive.

The growth in tablets and ultra portable thin machines will be the focus through 2013 and beyond.

PC gaming rigs are growing in popularity and for this reason we expect AMD, NVIDIA and Intel to continue to offer new products for many years to come. There are thousands of games available for the PC making it the gaming platform of choice. Today Windows 7 x64 is the gaming OS of choice and games using DirectX 9 or higher generally work fine.

TINY TRANSISTOR