Compared to the original GTX 460 768MB version the clocks haven't really been upped that much for Asus' overclocked TOP edition.
The 670MHz core speed has had a fairly minimal boost up to a rounded 700MHz with a 1,400MHz shader clock up from 1,350MHz. The memory, too, has had a wee boost up to an effective 3,680MHz.
This factory overclock alone doesn't really garner much in the way of performance improvements over the stock GTX 460 768MB card.
You're talking at most a boost of only a couple of frames per second, which is hardly earth-shattering.
It's a shame Asus hasn't had more confidence in its TOP edition's ability to overclock, so you're not getting much for the extra cash bar a different cooler and a picked GPU that should be capable of a healthy overclock.
As it turns out the TOP edition can deliver on that overclocking promise. We managed a hefty 150MHz overclock on the core speed and another 120MHz on the memory.
This gave us benchmarking results that were almost on par with a stock-clocked 1GB GTX 460. Granted a stock-clocked 1GB GTX 460 is only another £5 on top of this TOP edition, so that kind of nullifies these gains.
It's a shame then for these lower memory cards that the superior 1GB card exists at all, especially at the same price.
If the 768MB cards were significantly cheaper than their more well-endowed brethren then they could gain some traction in the market-place. As it is though they're little more than also-rans.
There is a significant amount of overclocking headroom in the chip, and that re-designed GPU cooler should help you maintain a hefty overclock for longer.
The minimal factory overclock on these cards compared to the competition means you're really not getting a lot extra in the TOP edition. It also means there's little warranty protection as you're more likely to overclock them further to justify your purchase.
Despite the hefty overclocking headroom the GTX 460 768MB TOP is not the card you're looking for. Out of the box it's not much faster than a stock 768MB card and is another £20 more expensive.