Feeds
85%

AMD Radeon HD 4850 and 4870

Snatching the price:performance crown from Nvidia?

Intelligent flash storage arrays

Review The new AMD 'RV770' graphics chip that lies at the heart of Radeon HD 4850 and 4870 owes a great deal to the 'RV670' that we saw in HD 3850 and 3870. It uses the same 55nm fabrication process and continues to support DirectX 10.1, but the transistor count has risen from 666m to 956m.

That’s a 44 per cent increase in the number of transistors so it’s impressive that the die area has only increased by 37 per cent from 190 to 260 square millimetres.

By the sound of it, AMD has taken baby steps with its new chip but one part of the specification leaps off the page: the number of Stream Processors - aka unified shaders - has jumped from 320 to 800.

AMD RV770

AMD's RV770: die hard

These numbers puzzled is so we fired off an e-mail to AMD thus:

"How the heck has the shader count climbed from 320 in RV670 to 800 in RV770 on the same 55nm process? Do the old and the new shaders use the same number of transistors?"

We got this response from Richard Huddy, AMD's head of developer relations for graphics chips: "Yes, the RV770 is only about 40 per cent larger than RV670, but the transistors are used on average about 50 per cent more efficiently too – and when you combine both of those factors together you get a much more impressive design.

"Traditionally we’ve focused only on saving Silicon area by moving to smaller processes, this time we made a very deliberate decision to get our performance per dollar much higher.’

It sounds like AMD has adopted the Intel Tick-Tock approach. RV670 - Tick - was a major step forward from the 80nm Radeon HD 2900, and RV770 - Tock - has refined the design to deliver higher performance and better value.

Top 5 reasons to deploy VMware with Tegile

More from The Register

next story
Don't wait for that big iPad, order a NEXUS 9 instead, industry little bird says
Google said to debut next big slab, Android L ahead of Apple event
Netscape Navigator - the browser that started it all - turns 20
It was 20 years ago today, Marc Andreeesen taught the band to play
A drone of one's own: Reg buyers' guide for UAV fanciers
Hardware: Check. Software: Huh? Licence: Licence...?
Jaguar Sportbrake: The chicken tikka masala of van-sized posh cars
Indian-owned Jag's latest offering curries favour with us
The Apple launch AS IT HAPPENED: Totally SERIOUS coverage, not for haters
Fandroids, Windows Phone fringe-oids – you wouldn't understand
Apple SILENCES Bose, YANKS headphones from stores
The, er, Beats go on after noise-cancelling spat
Here's your chance to buy an ancient, working APPLE ONE
Warning: Likely to cost a lot even for a Mac
Xiaomi boss snaps back at Jony Ive's iPhone rival 'theft' swipe
I'll have a handset delivered. Judge us after you try us...
prev story

Whitepapers

Forging a new future with identity relationship management
Learn about ForgeRock's next generation IRM platform and how it is designed to empower CEOS's and enterprises to engage with consumers.
Why cloud backup?
Combining the latest advancements in disk-based backup with secure, integrated, cloud technologies offer organizations fast and assured recovery of their critical enterprise data.
Win a year’s supply of chocolate
There is no techie angle to this competition so we're not going to pretend there is, but everyone loves chocolate so who cares.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?
Intelligent flash storage arrays
Tegile Intelligent Storage Arrays with IntelliFlash helps IT boost storage utilization and effciency while delivering unmatched storage savings and performance.