ATI Radeon X1950 Pro?Think of the Radeon X1950 Pro (RV570) GPU as a souped-up version of the current X1900 GT SKU and you won't be far wrong.
What's the same?ATI carries over the GT's 36 pixel processors, comprised of 12 texturing units with 3 ALUs per unit. It also features the GT-matching (and, indeed, XTX-matching) 8 vertex shaders, Further similarities extend to the use of a ringbus memory controller, ultra-threaded architecture capable of utilising 384 simultaneous threads. Radeon X1950 Pro is endowed with ATI's AVIVO video-processing technology, too.
Faster memoryGPU core speed remains at 575MHz, offering 6.9GT/s fillrate but RV570 improves upon the X1900 GT with respect to memory bandwidth, up from 1.2GHz to 1.38GHz, and via the 256-bit memory controller, putting out just over 44GB/s. Unlike the range-topping X1950 XTX, however, and presumably down to the plentiful supply of current graphics RAM, X1950 Pro features regular GDDR3 modules.
Die shrink and HDCP supportATI's taken this opportunity to move to an 80nm manufacturing process, down from the 90nm used on all other X1900-class GPUs. The RV570 core should put out less heat and require a less obtrusive cooler, then. Die size is reduced to around 230mm² and it packs in around 330M transistors, making it a little smaller and less transistor-heavy than the R580 core.
The RV570 GPU is also equipped with HDCP (High-Bandwidth Digital Content Protection), run through the card's twin dual-link DVI ports, which'll be required to play back high-def. material from Windows Vista. Of course, a current midrange GPU has enough clout to render Vista in all its aero glass pomp.
Internal CrossFirePerhaps the greatest feature integrated into X1950 Pro is internal CrossFire, which, finally, removes the need to purchase a specific master card and attachment via an external dongle, through DVI, for the most-efficient multi-GPU fun. ATI has integrated the compositing engine required for CrossFire on to the RV570 GPU itself, and two regular RV570s can be coupled together via a couple of SLI-like bridges for inter-card communication. Driver software then configures one card as master and the other, as you probably have guessed, as the slave. ATI reckons that the twin connector approach offers enough bandwidth to offer 2560x2048 resolutions at 60Hz. Whether this SKU, in CrossFire mode, is able to churn out enough data at that resolution is debatable, but it does give us an idea of what ATI might invest R600 with.
Informed readers will no doubt appreciate that ATI currently offers dongle-less CrossFire, run purely through PCIe bandwidth, for X1900 GT cards. However, as our dongle-less analysis proved, it's often found lacking in pure performance terms. ATI, then, has addressed an issue that has plagued CrossFire from the off, that is, a sensible method of inter-card communication in a multi-GPU environment. Hurrah, we say!
Pricing and tech. thoughtsDigesting the above facts, the ATI Radeon X1950 makes for a compelling midrange card in Q3 2006. What sweetens the deal is that it's to be introduced with an RRP of £149, so around current X1900 GT 256MiB money. It improves on a midrange favourite in a number of meaningful ways, too. However, you'll have to wait for the next iteration of cards (R600) before ATI introduces fundamental GPU overhauls.
ATI's Radeon X1950 Pro is the logical enhancement to X1900 GT. It provides all of the GT's feature-set but adds in faster memory, a die shrink, HDCP support, and bridged CrossFire. X1900 GT with cherries on top, if you will.