Wednesday, April 29, 2015

Random build of the day: a magnifying lens for Smartphone

One day, i woke up with the need of Google cardboard goggles... so i sought for two 45mm lenses in my everything-you-need-is-there (aka slag heap) and found an old broken cine-camera with an about 30mm focal lens: Not good for cardboard, but perfect for a magnifying tool!
The early prototype
Foamboard is the answer

The Lens:

The Prototype:

The Result
Some radom pics

And now here is a small chip:

  • First a pic of the set up
  • Then the chip
  • And finally a cropped version of the pic to see how good is the result!

Yeap, the gold wires aren't all in good shape ;-)

Monday, April 20, 2015

DIY of the day: Adding heat spreader to Value RAM modules

If you are not building a hardcore gaming computer, then some "Value" RAM modules can be enough. The modules (if made by well known brands like Corsair, G.Skill, ...) are still high quality but does not feature any heatspreader, from my own experiments those heatspreaders are not mandatory as RAM modules does not create much heat.
Though heatspreaders are usually cool and good looking: If you have some old modules with ones, why not swapping them to the newly bought modules?
Removing the Heatspreaders from old modules
Disclaimer: your warranty is now void!
Get the modules, find the metal clips (on my G.Skill modules, they are not painted). Lift one with your finger nail: it should jump easily.
Repeat for the second clip.
Swapping Modules
The tricky part
NB: Don't forget to remove the label from the new modules (this voids warranty.)
On my Corsair modules the labels could be easily removed without tearing: i reused them later.
Once the clips are gone, the heat spreader will unfold open. It's time to swap the RAM modules:
/!\ Be extremely careful on the side facing you ==> the labelled side is ALWAYS looking toward the CPU on ATX Motherboards
  1. Once roughly adjusted, fold back.
  2. Make sure to adjust the Heatspreader position without tearing or wearing the heat-pad (grey part on the picture), do not press it to tight either.
  3. place the clips back in place: you should hear a "click" and the clips should be in the state they were before unfolding.
If the labels survived the swap, then add them back to the heatspreader to identify the "CPU-looking" side of the modules. You can also use any other way to ease one-sight identification.
You now have your brand new value modules skinned as higher class ones, they won't reach a much lower CAS Latency, but might be able to support some more overclocking.
And... they simply look cool if not cooler than before

Saturday, April 18, 2015

Lower CAS latency on a legacy Computer: Is it worth it?

Some Story background
With time going on, i got enough DDR2 modules to play a little with them.
An old question was how CAS latency is important and impacts performace on a legacy computer (with a CPU that doesn't feature any L3 cache)

Clock and CAS Latency
Modules used:

Name PC2- Frequency (MHz) CAS latency Size (MB) per module
Nanya NT2GT64U8HD0BY-AD 6400 800 6-6-6-18 2048
Corsair Value Select VS2GB800D2 6400 800 5-5-5-18 2048
Gskill Extrem2 PC6400PK 6400 800 4-4-4-12 1024
Gskill Extrem2 PC6400HZ 6400 800 4-4-4-12 512
Hynix HYMP564U64BP8-C4 AB-T 4200 533 4-4-4-12 512
Micron MT8HTF6464AY-53EB3 4200 533 4-4-4-12 512
only the green modules will be compared in this article, we'll play with the others later on.

Testing Conditions
Hardware & Software

CPU : AMD Athlon X2 64 5600+ (@2.9GHz)
MotherBoard:  Gigabyte GA-M61PME-S2P
RAM : Tested Criteria
GPU : Geforce 8400GS
HDD : Seagate Barracuda 7200.8 250 GB (7200rpm)
CD/DVD :  writer

The Software used is nothing complicated: Memtest86 v4.20

Single and Dual Channel CAS battle (DDR800)
Both Modules are 2GB DDR800 (PC2-6400), the only discriminating criteria is the Cas Latency : CL5 (5-5-5-18) vs CL6 (6-6-6-18)
Signle Channel (1*2GB) and Dual-Channel (2*2GB) results are the following:

  • SC-5-5-5-18: 2369MB/s
  • SC-6-6-6-18: 2252MB/s
  • DC-5-5-5-18: 2861MB/s
  • DC-6-6-6-18: 2643MB/s

Upgrading from to Single Channel 5-5-5-18 Dual Channel 5-5-5-18
Single Channel 6-6-6-18 +5 %

Dual Channel 6-6-6-18

+8 %

There is definitely a performance increase in pure RAM bandwidth, though this has barely any impact on real life work on a legacy PC.
NB: i also tried to mix the Corsair (5-5-5-18) and Nanya (6-6-6-18) modules, the motherboard set them to dual channel even though the chips are quite differents... and gave the following result:
It down-clocked the RAM to 667MHz (351MHz), and reduced latency to 5-5-5-15; for a 2410MB/s bandwidth.

Sunday, April 12, 2015

DIY 4 pins CPU-Fan adapter to 4 pins CPU-Fan + 3 pins Case-Fan

Some Story background

After i saved the old Acer X1700 motherboard from trash by replacing capacitors, i noticed that the passively cooled GPU was overheating... 45-80+°C (idle/full)
It was time to add a case FAN ... - where ? ... There's no place in there!- Doesn't matter, there's place outside the case!
The real issue was the single FAN port on the motherboard, and no SATA/MOLEX port left.

Making the 4 pins to 4+2 pins
Why not 4 to 4+3?

Here is the scheme:

Intel 4 pins to 4 pins + 2 pins (no tachymeter for secondary fan)

  • The female 4 pins part is plugged on the motherboard CPU-Fan port.
  • The Ground (black wire, pin 1), the +12V, the Sense (tachymeter) and the Control (PWM pulses) are wired to the CPU-Fan (4 wires PWM-capable), and
  • the secondary (SYS) Fan only gets Ground and +12V.
  • We have no use monitoring the rpm of that fan, and it may interfere with CPU-Fan control (on my testing AMD motherboard the CPU-Fan didn't work until i removed the sense connection on the secondary Fan.

  • GND
  • +12V
  • Sense
  • Control
  • GND
  • +12V
  • not wired
  • none

Making of
What are those colors???

On the first test i had wired the GND to an orange wire, for the final build the color scheme is slightly different:

MotherBoardMain Cable partCPU-FAN wiresSecondary wiresSYS-Fan
  • GND
  • +12V
  • Sense
  • Control
  • Black
  • Yellow
  • Red
  • Blue
  • Black
  • Yellow
  • Green
  • Blue
  • Brown
  • Blue
  • None
  • None
  • GND
  • +12V
  • Not wired (ctrl)
  • None

Looks messy? and it is, but everything was done with what i had under the hand...


4 pins to 4+2 pins adapter DIY

The Fan used is fixed with plastic ribbons

GPU Temperatures are really lowered: