HDMI (High-Definition Multimedia Interface) is the current de-facto connectivity for most AV equipment.  In the old days, when we were still using analog component or coaxial cables, manufacturers came up with various ways to improve the cables. In the more expensive cables, you will find gold plated connectors, or EM/RF shielding on the cabling. Coupled with fancy marketing and packaging, the difference in pricing between a plain vanilla cable and a high-end cable could be 10-20 folds. But does all these optimization apply for HDMI, which utilizes digital signals?

As we all know, digital signaling uses a combination of  zeros(0) and ones (1) for transmission, so in theory the signal transmitted should either work or fail; there is no “in-between”. Analog signals uses sine-waves for transmission, so if there are external interference, it will result in image degradation (by augmenting the sine-wave in transmission).  For digital signalling, failed transmission should result in a failed pixel display (appearing like sparkles on screen). Some cables are also marketed as Ultra-High bandwidth, but in actual fact, the HDMI 1.3 (and the upcoming v1.4) specifications states that cables should only require to meet the 340MHz (10.2Gbps) bandwidth requirements. Below is a breakdown on the amount of bandwidth require that is required for uncompressed Full HD 1920×1080 video. This also takes into account for the vertical and horizontal blanking pulse to denote a new frame.

HDMI bit-rate = (horzPixels + hBlanking) x (vertPixels + vBlanking) x bitsPerPixel x frameRate x 10/8 (for TDMS encoding) x 3

Full HD 1920×1080, 60fps, 8-bit color per channel (24bit RGB) = [ (1920+280) x (1080+45) x 24-bit color x 60fps x 10/8 (extra 2-bit for TDMS enconding) x= 4.45Gbps

So in theory, any cable that meets the HDMI 1.3 specifications should be more than ample to support the bandwidth required. There is no  need for additional bandwidth at all, at least at this point.

Several tech sites had also performed testing with generic HDMI cables vs expensive Monster cables, and using specialized software to capture the transmitted output on the end display . The results are a victory for those of us who does not buy into marketing gimmicks and actually had some common sense. The output is 100 per cent identical, whether you are spending $10 or $100 on a cable.  HDMI guarantees you a pristine image – how good the image is comes down to the quality of your screen, and your perception of how it looks. People that purchase expensive cables might fall into the placebo effect, as personal perception is hardly measurable.

From my research, i would say it is safe to say that any properly manufactured cables with no loose cable or broken heads should work flawlessly for most home users that do not require HDMI cabling more than 4 meters . As cable length increases, the quality of the cabling becomes more prominent as the signal needs to travel further, and is more susceptible  to signal degradation issues. Below is a breakdown from mint.com of what i have discussed above in pictorial form.

Question is: are you going to be a douch nozzle or feed the children?

I’ve recently just upgraded to the TP-Link TD-W8960N Wireless-N ADSL Gateway from my 2Wire 2700HGV-E Mio Box. When i first installed it, performance was good. The startup time was quick from first power on, taking only <60 secs to enable the wireless radio and establish DSL connection. Gone are also the random DSL line disconnection problem that i had when using the Mio box. It was very frustrating having to reboot the Mio box every time the DSL light goes “red”. It sorta just hangs. So it appears that most of my problems went away, until my mate started complaining about his W8960N having problems when more than one wireless machine is connected, particularly his iPhone.

I didn’t experience this problem myself — all the 5 devices in my house are on wireless, and they worked flawlessly. But something went wrong when i made a slight change to my router’s DNS proxy hostname, and poof — my DNS stopped working. DHCP would lease out all the correct settings, so it wasn’t a DHCP problem. I tested with the standard ping test and dig lookups:

Ping to SingNet DNS:

eddie-tans-macbook:~ eddie$ ping 165.21.83.88

PING 165.21.83.88 (165.21.83.88): 56 data bytes

64 bytes from 165.21.83.88: icmp_seq=0 ttl=55 time=10.139 ms

64 bytes from 165.21.83.88: icmp_seq=1 ttl=55 time=8.889 ms

That looked ok. DSL line appears to be working normally.

Checking DNS lookups on the router address:

eddie-tans-macbook:~ eddie$ dig @192.168.1.254 www.singtel.com

; <<>> DiG 9.4.3-P3 <<>> @192.168.1.254 www.singtel.com

; (1 server found)

;; global options:  printcmd
;; connection timed out; no servers could be reached
Ahh.. DNS lookups were timing out.

eddie-tans-macbook:~ eddie$ dig @165.21.83.88 www.singtel.com

; <<>> DiG 9.4.3-P3 <<>> @165.21.83.88 www.singtel.com

; (1 server found)

;; global options:  printcmd

;; Got answer:

;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 29837

;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:

;www.singtel.com.		IN	A

;; ANSWER SECTION:

www.singtel.com.	318	IN	A	203.208.248.10

Dig @SingNet DNS resolves www.singtel.com correctly. So when i set my Mac Book’s DNS manually to include 165.21.83.88, my webpages resolves properly, but experiences problem with the default DNS leased by out the DHCP server (192.168.1.254).

So for some reason the DNS server on the router when there are multiple clients connected to it. After mucking around for a bit, i think i found the fix to the problem.

To work around this problem, make sure you have your LAN setup properly check under Advanced Setup -> LAN and “Enable DHCP Server” is checked. Fill in your start and end address (if unsure, just fill in 192.168.1.100 for Start IP Address, and 192.168.1.200 for End IP Address)

Next, go to Advanced Setup -> DNS -> DNS Server and see that “Obtain DNS info from a WAN interface:” is selected and make sure you choose your WAN interface from the dropdown list.

Lastly this is where i was stucked. Under Advanced Setup -> DNS Proxy, checked Enabled or disable DNS Proxy, under “Hostname” key in your router’s IP address, which should be 192.168.1.1 by default. (mine was 192.168.1.254). For the “Domain name of the LAN network“, you may key in any name that you fancy. Then click Save/Apply.

And viola! For some reason, this appears to work around the problem.

Upgraded my SingNet DSL line from 3M to 10Mbps. Had some teething problems with line packet drops and intermittent disconnection. But all is well after the technician came down and meddled with my phone line. Did a test on Speedtest.net and this is what i got:

OMFG!

Thinking that it might be some erroneous result due to browser, i tried with Google Chrome a second time and got this:

And then Internet Explorer:

WTF?!