computer hardware

Corsair PSU Electrical Buzzing Noise Under Load

Power Supply Coil Whine

This article demonstrates one type of electrical buzzing noise (coil whine)  that computer power supplies can generate under load. In this case, the unwanted noise comes from a Corsair HX100i Platinum PSU – a supposed premium product and chosen for a  silent PC build because of its Zero RPM fan mode and its promised quiet and efficient operation.

Power Supply Units (PSUs) should not sound like this. This one was sent back for an exchange and the replacement was good.

During general desktop use, the power supply was silent.  When required to fulfill demanding power requirements though, the PSU started to make a buzzing sound  like sparks jumping the gap of a Van de Graaff generator and in some instances, like chirping crickets.

It was difficult to determine the power supply as the source of these noises when it was in  situ within the PC case. Noise from cooling fans and spinning hard disk drives can make the noisy culprit difficult to determine by putting your ear inside the computer case. The only way I could make a determination was to remove the power supply from the case and place a demanding load on the PSU. This made it much easier to identify the noise source.

I used the Furmark GPU stress test to make the power demand.

This video demonstrates the electrical buzzing noise from the Corsair HX1000i power supply when put under load and how the noise stops when that demand is removed.

As per Corsair’s recommendations for curing noisy PSUs, all power saving options were disabled on the motherboard and in Windows prior to recording.

  • 02 seconds  : mouse click to start the Furmark GPU stress test. Straight away, the unwanted PSU buzzing noise can be heard.
  • 12 seconds : this is the noise from the GPU fan. However, the electrical noise from the Corsair PSU can still be heard.
  • 24 seconds : mouse click to end the Furmark GPU stress test. The PSU noise and the GPU fan both stop.
  • 29 seconds : the Furmark GPU stress test is repeated and the Corsair power supply noise can heard after the mouse click.
  • 48 seconds : Corsair power supply details shown during the Furmark GPU stress test. Power draw 187W in and 172W out.
  • 59 seconds: Furmark GPU stress test ends and PSU noise stops.

Speed Up DNS Propagation

Speed Up DNS Propagation by Ensuring DNS Cache is Purged

DNS Propagation Taking Too Long | DNS Replication Problems | How To Clear DNS Cache | DNS Troubleshooting | DNS Benchmarking | Changing DNS Provider

Modified DNS entries can take hours or even days to replicate across the internet. And often, this delay can be extended unnecessarily by old DNS cache residing on your computer and slow, Public DNS servers.

This article details the checks you should perform after updating DNS records to ensure that cached DNS lists and slow-to-refresh Public DNS  servers are not misdirecting your browser and causing unwanted delays.

This article is useful in these circumstances:-

  1. Moving a web site from one host to another: When name servers or DNS records have been updated to point your domain to a new hosting company. The hosting company confirms that the DNS transfer is complete and that your site is working normally but your domain name still directs to your previous host and old website.
  2. Pointing a domain name to a website: When name servers and DNS records have been set to point your new domain name to your new web site. You are still waiting for DNS records to propagate throughout the world’s networks for your new web site domain name to be resolved.
  3. Troubleshooting a problem with DNS.
  4. Learning how to clear your DNS cache.
  5. Making browsing speed faster. You could benefit by changing your ISP’s default DNS servers.
  6. Benchmarking DNS servers in order to choose the one optimal for you.

What is DNS?

The Domain Name System (or Service or Server) is a look-up table that resolves internet web addresses like Facebook to their respective IP address, i.e. – the backbone on which computers are able to connect and communicate.

Without a DNS directory, we would all have to remember meaningless numbers instead of easy-to-remember names.

When a web address is requested in a browser, it’s equivalent IP address is sought by these steps and in this order.

1. Local hosts File

On a Windows Operating System, the hosts file in:


is the first port of call. If the web address is recorded in that file with a corresponding IP address, then the browser will be directed and the search ends there.

2. Locally Cached DNS

If there is no record of that web address in the hosts file, then locally cached DNS is searched next. This can be stored on the computer itself and / or inside the router. If a suitable record exists in stored DNS cache, the search will conclude there and the browser will be  directed to that stored IP address.

Some routers are capable of storing a cached copy of Domain Name System lists. If one does exist, this cache will be the next list to be searched to enable fast interpretation of the web address, instead of requesting that data from a Public DNS.

3. Public DNS

Only when the previous two steps cannot be fulfilled does the request go to a Public DNS to resolve the web address to an IP address.

How Web Addresses are Resolved with a Domain Name System

How a Web Address is Resolved to an IP Address with DNS


How to Clear Cached DNS

Follow these steps to ensure that you are not waiting unnecessarily for DNS replication and propagation after updating DNS records and name servers of your website.

Check the hosts file

It is always worth checking your hosts file in notepad to see if there have been any redirects added in the past that you may have forgotten about – or indeed, not known about.

Tip! notepad has to be opened with Administrative privileges if you are going to make any changes to your hosts file.

If there is a reference in your hosts file to your problematic site, then  make a back up of the file; remove that entry and save the hosts file. You may need to re-boot your computer for the new hosts file to be read by the operating system.

Clear Local DNS Cache

Open a command console with Administrative privileges by clicking on the Windows START icon (bottom left) and typing cmd into the search field. Do not press Enter.

cmd.exe will appear at the top of the list. Right click on it and select Run as administrator. The command console will open.

In the command console type:

ipconfig /flushdns

and press Enter.

Windows Command Console: Ipconfig /flushdns

ipconfig /flushdns

The console will report Successfully flushed the DNS Resolver Cache. Close the console window.

Check and Clear Router DNS Cache

Some routers are capable of caching DNS lists. You should determine whether or not your router does this and if it does, purge that list.

Log into your router and look for for an option or something that resembles Advanced DHCP Settings or DNS Settings.

The example shown below is of a NetGear router with the option to clear router DNS cache.

Clear Cache DNS NetGear Router

NetGear Router Configuration: Advanced DHCP Settings – Purge DNS Server List

Change the Public DNS Primary and Secondary Addresses in your Router

By default, most routers are programmed to obtain and use your ISP’s Primary and Secondary DNS addresses automatically.

However, these servers could be slow to replicate changes in DNS records and therefore slow to propagate the changes you have made. They might be over loaded too, causing substantial look-up delays that decrease browsing speed.

There are many alternatives to DNS servers supplied by ISPs. The benefits of using an alternate provider include:-

  • Faster refreshing of DNS record changes
  • Faster browsing speeds
  • Improved security
  • Family filtering

Google Public DNS is a free Domain Name System that can be easily configured for use in your router without having to install any software. OpenDNS is another free Domain Name System that is commonly used.

To configure your router manually to use another Public DNS, log in to it and find an option similar to this: Domain Name Server (DNS) Address and select Use These DNS Servers. Enter the two IP addresses given by your chosen provider.

OpenDNS Router Configuration

Manual Configuration of Primary and Secondary DNS Addresses | OpenDNS IP Addresses Shown

Save the changes if necessary then re-boot the router.

Once all these steps have been completed, try to access your domain again.

DNS Benchmark – Chosing a DNS Provider that is Optimal for you

DNS Benchmark

DNS Bench,ark by Steve Gibson | Gibson Research Corporation

The DNS Benchmark by Steve Gibson at the Gibson Research Corporation is a valuable tool for finding the DNS  provider optimal for you. It is a free and small, stand-alone program that requires no installation. Try it and discover faster browsing speeds and all the other benefits that are gained by changing your DNS provider.

How to Reduce the Minimum Fan Speed of a nVidia GT430 Graphics Card

How to Reduce the Minimum Fan Speed of a nVidia GT430 Graphics Card

If you have an  nVidia GeForce GT 430 graphics card and you want to reduce the card’s minimum fan speed, then these instructions should help you achieve that with relative ease.
ASUS 1GB GeForce GT 430 PCI-E 2.0 with Low Profile Bracket


Cards like the ASUS 1GB GeForce GT 430 graphics card are often incorporated in slim Home Theatre PCs (HTPC) because of their low profile fit and their relatively low cost coupled with their high performance at decoding High Definition (HD) video content.
These models have a cooling fan sat inside the heat sink that helps govern the temperature of the GPU. The minimum fan speed is set in the card’s BIOS as a percentage of it’s top rotational speed. My card’s minimum fan speed was set at 60%. I had read of other minimum fan speeds, such as 65%, when I started to research this.
Initially, the card was quiet enough for use in my HTPC. Over time however, the fan became louder at it’s minimum, idling speed. And I wanted to quieten it down by reducing it’s minimum speed and adjusting the fan’s speed v GPU temperature curve. I found I could do most things with software except reduce the hard-coded minimum fan speed. A BIOS hack was required.
I found that a great number of people had been asking how to do this hack via many different internet forums. Solutions were not clear; the posts were old and a lot of the links for the necessary software were dead.
I found two noteworthy sets of instructions here to flash the device from a bootable usb stick running DOS. No matter how I tried though, I couldn’t get mine to flash. And I think it’s because the software revisions have moved on.

Guide for Flashing BIOS of nVidia GPU –
Bootable USB Drive, Flashing nVidia GPU – Recovering From a Bad Flash –

It’s worth checking out how to recover from a bad flash and be prepared for such an event.

What You Will Need

I did everything in Windows 7 x64. There was no need to create a DOS bootable usb drive. All I had to do was re-boot the PC when the BIOS flash reported as being successful.

nvflash (windows version)

EVGA Precision X


Download NiBiTor and nvflash (windows version) and unzip them if necessary by extracting them to their own folders. Remember their locations.
Download and install EVGA Precision X on your computer.
Click once on Windows Start and type in cmd where it says Search programs and files. Do not press Enter.
The cmd program should be shown at the top of the list under the heading: Programs. Right click on it once and select Run as administrator. Click Yes when prompted.
The command console should appear and look something like this:

Double click the nvflash folder and right click on the directory path at the top of the folder window.

Select Copy address text from the context menu.

You can see here that my nvflash folder resides on my F drive at
F:\GT430 BIOS FLASH\nvflash_windows_5.142

Now click on the cmd window and type cd and a space. Right click and select paste.
The full directory name should be pasted into the window like this:

Press Enter to change into that directory. Notice that if you have your files on a different drive to C, you will have to change to that drive before hand like I have done here with F:

Back Up the Original ROM

In the cmd window, type

nvflash -b original.rom

and press Enter

This will make a back up copy of the nVidia card’s BIOS to your nvflash directory with the filename
You can use a filename of your choice.
It is important at this stage to make back up copies of this BIOS image. Store a copy on a usb stick. Store a copy on another PC. Should things go wrong, you will need access to this file. A bad flash may prevent your card from outputting any display at all. So it’s no good just to have the one copy on that machine. You won’t be able to see to get at it!

Modify the BIOS with NiBiTor

Go into your NiBiTor folder and run the program.
Go to File > Open BIOS…
and select the file original.rom from your nvflash directory

You should see something like this as you browse the different tabs:

Change the Min fan speed here to something like 30

Then go to File > Save BIOS…

and select a new name for you modified ROM. Ensure you don’t overwrite your back up file.

Save this file to your nvflash directory. I used the filename:


Ready to Flash the BIOS?

The files in your nvflash directory should look something like this:

The nvflash files; the modified BIOS and your back up file.
Note: I have two back up files of the original BIOS in this screenshot entitled backup.rom and GF108.rom. You will just have the one back up file entitled original.rom
WARNING: The next command starts the flash process!
Ensure that this process is not going to be interrupted by anything.
Click on the cmd window once more and type:

nvflash modified.rom

and press Enter

The BIOS will be flashed with your modifications. Wait until the program reports success, then reboot your PC.
In the event that the flash goes wrong, you will need your original BIOS rom file to attempt a blind flash using a usb stick. Details of how to do this are explained in the links I gave in the introduction.

Controlling Fan Speed

Launch EVGA Precision X

  • Tick Windows Start Up so the software runs every time Windows boots. If you click on the settings icon (the two gears in mesh – top right) you will be able to select Start minimized if you don’t want this screen to appear every time Windows starts.
  • Change the minimum speed of the fan. (I believe that there is another value in the BIOS that prevents the fan from stalling at low rotational speeds). I found  I couldn’t enter values less than 31% even though I’d set the minimum value in my modified BIOS to 20.
  • Ensure Auto is ticked.

Now click on fan curve and ensure that Enable software automatic fan control is ticked

Here you can drag the points on the curve to create your own profile of fan speed vs GPU temperature. Experimentation and monitoring is key here. Spend a while monitoring your GPU temperature under different conditions of load. Playing games for example will cause the GPU to generate lots of heat. That heat has to be dissipated effectively or your GPU will burn out.
This profile works for me but the sole use of my card is the decoding of HD video. What I’ve done here is:
  • halve the fan’s minimum speed
  • keep the fan at it’s new minimum speed until the GPU temperature hits 68’C
  • then increase fan speed accordingly to maintain 68’C – 74’C operating temperature range when decoding HD content
In a nut shell; silent operation at the expense of running the GPU 10 to 15 degrees hotter than before. It may lessen the card’s life but my HTPC is almost silent now.