What price power?

Shopping around for upgrades proves that there are bargains at both ends of the market - the Top People's store or the streetwise auction. It all depends on what you want: no worries or low outgoings.

I started at the top. Steve Berry, of Harrods' computer department, tells me they have memory and multimedia kits in stock, and can order to suit. Memory costs pounds 115 for 4 megabytes (Mb). If you live inside the M25, someone will call and upgrade your machine at home, for pounds 30 an hour. "Ring us, have your computer manual ready, and we'll tell you what you need," says Mr Berry. The department is run by Silica as an in-house concession. It can deliver orders worth more than pounds 45 anywhere in the UK for free.

Silica covers a limited range of upgrades, concentrating on memory, disks, fax/modems and scanners. But given the number of people who have a large selection of failed upgrades sitting in the bedroom cupboard, the house call rates highly.

Next, the specialist superstore. I ring PC World at Staples Corner in north London, one of the country's largest chip shops. Their technical department is quite helpful: memory costs pounds 171 for 4Mb, but PC World installs it only if you bought your machine from them. Can they suggest anyone to do upgrades? "Look in the Yellow Pages."

I consult Micro Mart magazine, where I discover that for pounds 104 I can have 4Mb of new "w/parity (1 x 36) 70 n/s" memory. Cheap, but what is it? I ask Choice Peripherals - "Get Factory Prices Direct". John delivers the idiot's guide to memory, and his philosophy on superstores ("They're very good at selling, but they don't sell the right thing"). Who will help me upgrade? "You can send the machine to us, but with memory you don't need to - we'll talk you through installation on the phone." Prices are low, and there is a good range of upgrades. But a mistake can cost money - you are charged a "re-stocking fee" for returned goods.

Computing's bargain basement is the auction room, but is it the place to go for upgrades? At London Computer Auctions, John Russell explains that it is worth looking at the catalogue. He says: "New memory and multimedia kits work out at about half the high-street price. But I couldn't recommend it to anybody who is nervous about doing their own upgrades. I know a guy who bought a multimedia kit nine months ago, fitted it the same night, and he finally got it working this week."

Everything you might possibly want goes through the auction room and prices sound unbelievable. For pounds 20 you can have a CD-Rom drive or a hand scanner, but if it's an obscure model by the Hokey-cokey Manufacturing Corporation, it may be an incompatible waste of money. Mr Russell's advice: no matter where you shop, check the sales policy - some suppliers won't give refunds. Components such as memory do not have serial numbers, so a buyer could theoretically replace dud chips and take them back to the shop for their money back.

Contacts: Harrods (0171-730 1234); PC World (0990 464464); Choice Peripherals (01909 530242); London Computer Auctions (0181-345 6535).