Having installed Wi-Fi, I now wish to buy a wireless internet radio, but am unable to find any sites that review models. Any suggestions?
Alun Richards

Wireless internet radio is a relatively new product category and I have yet to see any comparative group reviews. At the moment, I think your best bet is to look at the Internet Radio category at Amazon.co.uk. This lists 22 products, including five versions of the Tangent Quattro. Some have only one or two customer reviews and some have none, but at least you can see pictures and read the specifications.

Products not on the Amazon list include the Freecom MusicPal, Bush TR2015, Morphy Richards Internet Radio (sold by Currys and Argos), Logik IR100 (sold by Dixons), the Tevion Internet Radio and Media Player (sold by Aldi), and the Noxon 2 Internet Radio and Music Station for an iPod. Amazon.co.uk does not yet have the Revo Blik Wi-Fi in stock. There's also the Denon Smart S52 DAB Wi-Fi tabletop radio on the way, but it's expected to cost around £500.

Many products have multiple functions, and may include DAB and FM or FM/AM radios or even Digital Radio Mondiale. Some connect to MP3 players such as the Apple iPod. At least one - the Imp Adapt - also connects to a hi-fi system. Some can run on batteries. They come in many different shapes and sizes, and most are offered by different suppliers at different prices. The market is still in development, so you can expect many products to come and go before it settles down.

Before you take the plunge, read Reciva.com's internet radio Knowledgebase for answers to most questions.

Also bear in mind that if an internet radio station broadcasts at 128kpbs, it is going to consume about 55MB per hour. That's likely to blow a hole in any capped broadband service.

I run my home wireless network from a D-Link DI-624 wireless router, and access is restricted by passwords and MAC address filtering. I'm the only one who knows the passwords. However, I keep seeing new addresses appearing on the list of allowed MAC addresses. I have removed them from the list, but they come back. I assume that this means someone is bypassing my security, and that they must be fairly serious if they are getting through all those security measures.
Ian Sudbery

Most internet, Wi-Fi and Bluetooth devices have a Media Access Control (MAC) address, which starts with something that identifies the manufacturer. You can paste these characters into the Vendor/Ethernet MAC Address Lookup and Search site at coffer.com/mac_find/ and see if you recognise what comes up. One might be your router, or whatever. Your PCs may have two: one for built-in Ethernet and one for a wireless card.

However, these universally administered addresses can be overridden by locally administered addresses -- ones you have assigned. MAC filtering isn't secure because if you can change them, so can the hacker.

If identifying the devices doesn't solve the problem, then you may have to upgrade from WEP (Wired Equivalent Privacy), which isn't secure, to WPA2 (Wi-Fi Protected Access), which was added to the standard this year.

You will probably need to download a software update for your operating system -- perhaps the one for Windows XP SP2 -- plus new drivers for wireless cards. Many routers will also need firmware updates. There's one for the DI-624, but make sure you download it from your local D-Link country site and install it via a cable connection.

How much information can be in each record if there are 25m child benefit records on two CDs?
David Baxter

A standard CD-R will hold 703MB of data -- about 737m characters -- so two discs will hold 1.474bn. That would only be 59 characters per record. However, it seems there are only 7.25m records, each record being a family with one or more children. That would provide 203 characters of data per family, which is enough to include names and dates of birth, an address and bank details.

The simplest way to put a single database on to two CDs is to zip it using an archiving program such as WinZip. This would allow password protection, and would also compress the data. Text can easily be compressed into less than half the space, allowing more data to be stored on the discs. In this case, it could provide from 300 to 400 characters per family.

And remember, with coding, many data fields take up very little space. Country of birth, for example, only needs two characters.

I have used Outlook Express for more than 10 years. I have got used to the Send button in the top left of the screen. Now, when mailing three websites, the button has disappeared.
Chris Simpson

I've never heard of this before, but a search of the Microsoft Knowledge Base suggests article 306098. With Windows, buttons and menus are more likely to disappear because the system has run out of resources and needs a restart.

I pay £24.99 a month for 8Mbps broadband from Virgin. It is unbelievably slow. A pal sent me an 8MB attachment and it took nearly an hour to download. I've asked for help, but had no reply to my email.
Bob Sutton

First, download new anti-virus and anti-spyware programs such as the free ones from AVG. Disconnect your PC, restart in Safe Mode, then run both programs. Second, turn off all file-sharing programs and reboot your router. Go to PC Pitstop and run the Full Tests from the link on the left, under Tests and Scans. This will check your PC's performance, including (roughly) broadband speed, and compare it with similar machines. (BT also has a broadband performance tester if you type in your broadband phone number at speedtester.bt.com.) A third test is to try another PC on the same line: perhaps a friend could bring round a laptop?

By now you should be sure if it's Virgin's fault, so you can call its broadband technical support team on 0906 212 1111 and pay 25p a minute. You probably won't get anywhere because there is no real guarantee of the speed of the service. But perhaps you could downgrade to a slower, cheaper package or think about moving to another supplier.

Do you think the new 45nm computer chips being launched by Intel and AMD next year will affect the price of laptops when they come on to the market? I don't want to spend £500(ish) if it will be £250 in a few months' time.
Nikki Horrobin

For the past 30 years, there has always been a hot new processor on the way, making people wonder whether to wait. But there has never been less reason to bother. First, chip suppliers and PC manufacturers try not to change their "price points" -- they just bring in the new stuff at the top of the range and let the older technology filter down. In the short term, the PC you want will still cost £500 (or whatever), you will just get a bit more for the same money. Prices come down over the long term as people find the cheaper stuff does all they need.

In any case, extra processor speed is unlikely to make any difference unless you habitually do processor-intensive tasks such as encoding video. If you already use a PC, even a crude guide such as the performance tab on the Windows Task Manager will show the processor is running at 1% to 5% utilisation most of the time. You will usually get better results by spending any extra money on more memory (ie, 2GB) or on faster graphics than on a faster processor.

Fortunately there is a simple way to test the suitability of any machine for running Windows Vista: Microsoft has built in a test suite that gives a rating, the Windows Experience Index. This gives ratings for the different components, so check the graphics score in particular. This is most likely to be the weakest link, especially on cheap notebooks.

Remember, your PC is really only as good as the slowest component.

Can you, or any of your readers, recommend a site that gives simple instructions on using Linux? I installed it on my laptop six months ago and, despite repeated attempts, I have failed miserably to install any programs at all (so can only use the pre-installed stuff). I've read several "easy to follow" (yeah, right) pages, but none made any sense.
Paul Mann

Your experience might well be common, but I suspect many ordinary users just try a Live CD (which doesn't require installation) then give up. Part of the problem is that Linux comes in dozens of different versions that may work in different ways, and different people install different desktops (usually KDE or Gnome) and applications, so it's hard to produce a universal guide. Another part of the problem is that most Linux experts don't have a clue about writing for real newbies who only know Windows.

In theory, your best bet is Ubuntu: this is the current bandwagon, it's most likely to attract other newbies and therefore most likely to attract support. However, I don't know of a good guide for switchers. There is a Linux Newbie Guide, which has a stab at explaining how to install software using one of the graphical front ends. Does anyone know anything better?

I am on Windows Vista and have downloaded Virgin Broadband PC Guard. It has advised me to uninstall Bullguard as this will clash. Which would be preferable to keep?
Gordon A Brown

You shouldn't have two security suites running at the same time, so one has to go. I assume Virgin Broadband PC Guard is a version of Radialpoint's suite since Virgin is listed as a customer, but I can't find any independent reviews of the software. The only thing I can see in its favour is that it's free. Bullguard is a commercial package and has been widely reviewed, although not always favourably, and the bought-in components may be subject to change. On balance, Bullguard is probably the better bet, because of its BitDefender anti-virus software, and I'd certainly go for Bullguard on a portable. However, you can still get better results by choosing separate programs than by buying a security suite.

Having extended my laptop's screen to the new Toshiba LCD in the kitchen, I was impressed with the results. Is there a small, stylish/pretty computer suitable for the kitchen?
Ieuan Davies

Building small PCs to connect to HDTVs is a fairly common geek project, helped by the availability of low-power Mini-ITX (17 x 17cm) boards and barebones cases. These typically run a version of Windows with Media Center features (including Vista Home Premium) or the Linux-based MythTV. Articles such as Build Your Own Media PC at Trusted Reviews will give you an idea what's involved. Many small British suppliers will assemble systems to order. The Apple Mac mini could be an alternative, and is certainly more stylish.

A few companies have tried producing commercial kitchen computers, such as Seattle-based Beyond. It offered Icebox computers in both countertop and flipscreen versions, which could be mounted under a kitchen cabinet. It announced UK distribution in 2003. Did anybody ever see or buy one?

Can you recommend a free alternative to Windows Media Player for playing videos, particularly .avi? I am after a less bloated player.
Tony Jones

I think the best answer for Windows users is Media Player Classic. This can also play many QuickTime and RealVideo files, with the "alternatives" installed so you can avoid three lots of bloatware. If you download the K-Lite Codec Pack, this includes the Media Player, so you don't need to download it separately. The main free alternative is VLC, which is cross-platform. There are versions for Windows, Mac OS X, BeOS, and numerous versions of Linux and Unix.