Independent benchmark tests by Futuremark have revealed that Microsoft's Surface tablet is surprisingly slow at web browsing.

When run through the Peacekeeper: Universal Browser Test, the Microsoft Surface speed test came out at just 348, almost third of the result from the new Apple iPad 4's score of 951.

The Surface also scored slower than the Apple iPad mini (515), Nexus 7 (489) and even last year's Apple iPhone 4S model (438). In fact, the Microsoft Surface only just beat the Eee Pad Transformer Prime (344).

Microsoft CEO Steve Ballmer recently told CNBC: "You can go through the products from all those guys… and none of them has a product that you can really use," Ballmer continued. "Not Apple. Not Google. Not Amazon. Nobody has a product that lets you work and play that can be your tablet and your PC. Not at any price point."

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Apple's CEO Tim Cook retorted that Microsoft's Surface tablet is a "compromised" and "confusing" device.

For such a high-profile launch packing relatively modern technology, the results from the Surface must be disappointing to Microsoft. Fortunately the sluggish response may be due to Windows 8 software rather than the underlying technology, and Microsoft may be able improve the performance over time.

Microsoft Surface Web benchmarks