cooling and more memory?

[manukit]

Hello, i wanted to ask you if the paralella board needs a cooling fan or thermal solution and how much is the maximun RAM that the board can use besides the original 1GB.

Thank You

[markrose]

The RAM is limited to 1 GB. Other parts of the 32 bit memory address space are used for the parallella cores, the FPGA, etc.

I've read elsewhere the Zync70x0 FPGA gets very hot if you fully utilize it. I'll probably stick a heatsink on that when mine arrives.

[Gravis]

[FatherSuperior]

It seems that the board needs a fan, based on the little not I found when the board arrived. There are a bunch of fans with heat-sinks for RPi on eBay. Any idea where I could connect the pins for the fan on the board or anywhere else?

[9600]

[9600]

[mranderso]

Here is my experience.

I ordered the 8 board cluster. Arrive some time last week.

After spending a great deal of time writing 8 disks, I tried booting
up each board one at a time, straight out of the box. Fearful of
USB hubs at this point, I used a serial connection alone (no USB,
no HDMI).

One of the boards failed ./test.sh. It was one of the first
boards I tried. I continued with the rest and they all passed the
one run of ./test.sh. I returned to the first board and it passed.
And then tried again and it failed. Passed test intermittently, so
I wrote a script to run test.sh 100 times and record results.

So I installed heat sinks on 7 of the boards. ( One of the heatsinks
lost the backing in transit and was stuck to the plastic envelope
around the board in the box. Enough of the plastic stuck to the
adhesive when I pulled it free that I decided to not use it. Ordered
some thermal adhesive to attach later).

5 of the boards, including the one with no heat sink ran thru the
set of 100 test twice with no mismatch ERROR.

3 of the boards with heat sinks had double digit mismatch ERRORs.

I didn't have any computer fans around, so I found a 9 inch 60W
floor fan to create more than a little air flow.

With the air flow, the 3 troublesome boards all ran test.sh 100
times without ERRORs.

Will have to find a less obnoixous fan arrangement, but not sure
just yet how much air I need to move.

So you might get lucky and have success with not heat sink or fan,
but it appears to be the luck of the draw. I'm going to using multiple
power strips anyways, so I plan to power fans off AC.

[ubii]

mranderso,

If you want to monitor the temperature of the Zynq chip, I posted a simple bash script in the thread below, which will display the temperature in both Celsius and Fahrenheit.

viewtopic.php?f=23&t=930&p=6242#p6242

[Sundance]

Mark - and all Software Engineers

Another story from the REAL life of Embedded Signal Processing that I have been trying doing for the past almost three decades...

After years of development we finally shipped lots of "Production Box's" to our lucky (and now hairless Customer ) - and the Software Engineer that was allocated by our Customer as "Project Manager" got 10x of them running in a test setup in his office. The following morning he reported that 4 our of 10 had failed. Well.. - not good news. We could simply not understand. Suggested a few things, like measuring the power-rails, connectors, fan, temperature of the DSP, etc. - Asked him to repeat the test.

Next day 5 out of 10 had failed, but not all the same that failed the day before... - and had to get on my push-bike to visit them. I came to the Customers office and to my shock and horror I discovered that the Software Engineer had taken the lid of the 'Box', so the effectiveness of the fan was effectively 50%! When I asked WHY the lids was OFF the box, then he said it was easier to measure the temperature and see what was going on.

So...


- and we need you "Software Engineers", as us "Hardware Engineers" are lost with you!

[aolofsson]