I get the impression that Altera is in the lead when it comes to speed on DDR[3] interfaces. Can anyone confirm/deny this? Altera claims to be able to clock a 64/72bit wide DDR3 at 533Mhz on the StratixIII: http://www.altera.com/b/stratixiii-ddr3-video.html For Xilinx, the fastest reference design I can find is 32bit wide DDR3 at 400Mhz for the Virtex5. Can Virtex4 do better? So far, it looks to me like Altera did a KO on Xilinx when it comes to DDR3. Please tell me I'm wrong, Id hate to switch tools :p (and I need hard facts, not sales numbers)
DDR3 speed, Altera vs Xilinx
Started by ●March 14, 2008
Reply by ●March 14, 20082008-03-14
On 14 Mrz., 09:28, "Morten Leikvoll" <mleik...@yajoo.nospam> wrote:> I get the impression that Altera is in the lead when it comes to speed on > DDR[3] interfaces. Can anyone confirm/deny this? > > Altera claims to be able to clock a 64/72bit wide DDR3 at 533Mhz on the > StratixIII:http://www.altera.com/b/stratixiii-ddr3-video.html > For Xilinx, the fastest reference design I can find is 32bit wide DDR3 at > 400Mhz for the Virtex5. Can Virtex4 do better? > > So far, it looks to me like Altera did a KO on Xilinx when it comes to DDR3. > Please tell me I'm wrong, Id hate to switch tools :p > (and I need hard facts, not sales numbers)no, V4 can not do better . KO? did you count 10? :) Antti PS even DDR2 designs at 200MHz is not trivial for V4/V5, I would be very careful before trying some Xilinx chip at memory clock above what Xilinx itself claims. It doesnt mean that is not doable of course. Already V4 slowest speed grade FPGA fabric can have signals as high as 1GHz (my own test measurements!) for very short distances, so 533 should not be impossible for V5 highest speed grade. But its not the fabric or I/O speed alone that is needed for the successful implementation. PPS Xilinx are you KO? 1,2,3... tick-tock clock is ticking
Reply by ●March 14, 20082008-03-14
Morten Leikvoll wrote:> I get the impression that Altera is in the lead when it comes to speed on > DDR[3] interfaces. Can anyone confirm/deny this? > > Altera claims to be able to clock a 64/72bit wide DDR3 at 533Mhz on the > StratixIII: http://www.altera.com/b/stratixiii-ddr3-video.html > For Xilinx, the fastest reference design I can find is 32bit wide DDR3 at > 400Mhz for the Virtex5. Can Virtex4 do better?Altera has dedicated logic for source synchronous clocking for memories, that might make the difference. But be aware that that dedicated logic also creates more restrictions to pin placement and can waste big amounts of pins if you use many IO-voltages. In Xilinx V4/V5 the pin placement is sometimes easier to do. IO-structure is always a compromise between speed and flexibility. --Kim
Reply by ●March 14, 20082008-03-14
Morten, We chose different paths: Altera used hardened logic to get their speed, where we chose to stay general, and use any pins/any fabric/any standard. We have DDR3 designs that are also working at 533 MHz. Best to sit down and talk with your FAE on the subject. There are many other factors to consider (not he least of which is we are in full production on Virtex 5 LX, LXT, SXT, and they are just now in ES on on few parts, with S3 GX canceled completely). Even though Altera has some really mean, cool, and neat power point presentations, we basically have no competition whatsoever at 65nm at the high end (as you can't ship power point in your systems). Austin
Reply by ●March 14, 20082008-03-14
On 14 Mrz., 16:24, austin <aus...@xilinx.com> wrote:> Morten, > > We chose different paths: Altera used hardened logic to get their > speed, where we chose to stay general, and use any pins/any fabric/any > standard. > > We have DDR3 designs that are also working at 533 MHz. > > Best to sit down and talk with your FAE on the subject. > > There are many other factors to consider (not he least of which is we > are in full production on Virtex 5 LX, LXT, SXT, and they are just now > in ES on on few parts, with S3 GX canceled completely). > > Even though Altera has some really mean, cool, and neat power point > presentations, we basically have no competition whatsoever at 65nm at > the high end (as you can't ship power point in your systems). > > AustinLOL, eh, think there is only one tool we need: "powerpoint to silicon compiler" ;) Antti PS 553 MHz DDR3 without hardened io and general purpose FPGA is nice achievment
Reply by ●March 14, 20082008-03-14
Antti <Antti.Lukats@googlemail.com> wrote:>On 14 Mrz., 16:24, austin <aus...@xilinx.com> wrote: >> Morten, >> >> We chose different paths: Altera used hardened logic to get their >> speed, where we chose to stay general, and use any pins/any fabric/any >> standard. >> >> We have DDR3 designs that are also working at 533 MHz. >> >> Best to sit down and talk with your FAE on the subject. >> >> There are many other factors to consider (not he least of which is we >> are in full production on Virtex 5 LX, LXT, SXT, and they are just now >> in ES on on few parts, with S3 GX canceled completely). >> >> Even though Altera has some really mean, cool, and neat power point >> presentations, we basically have no competition whatsoever at 65nm at >> the high end (as you can't ship power point in your systems). >> >> Austin > >LOL, eh, think there is only one tool we need: > >"powerpoint to silicon compiler" ;) > >Antti > >PS 553 MHz DDR3 without hardened io and general purpose FPGA is nice >achievmentBut is it worth something in a real application or is it just 'cool'? When reading Xilinx memory interface application notes I get the feeling the cool factor (to get numbers to put in nice powerpoint presentations) is often more important than practical use. 533 MHz is pushing the limits on a Xilinx device but with dedicated I/O logic (like fast local clock paths for DQS) it would be a breeze to design. The way Xilinx works they say it can be done, but every more complicated interface like PCI, DDRx, PCI Express, serial ata, etc, etc is suddenly extremely difficult and should be left to the professionals. It is like Ford saying their cars are great and better than the rest, but in the real world you'll find you need 3 arms to drive around. A lot can be said about Altera, but almost every hobbiest FPGA user in the world is using Altera devices. This certainly says something about the ease of use of Altera parts and software. -- Programmeren in Almere? E-mail naar nico@nctdevpuntnl (punt=.)
Reply by ●March 14, 20082008-03-14
On Mar 14, 10:41=A0am, n...@puntnl.niks (Nico Coesel) wrote: <snip>> > A lot can be said about Altera, but almost every hobbiest FPGA user in > the world is using Altera devices. This certainly says something about > the ease of use of Altera parts and software. ><snip> I'd love to see your reference ;-) Or perhaps you know most of the hobbyists personally? I like seeing hobbyists use the tools and parts that are best for their activities whatever they may be. - John_H
Reply by ●March 14, 20082008-03-14
On 14 Mrz., 19:03, John_H <newsgr...@johnhandwork.com> wrote:> On Mar 14, 10:41 am, n...@puntnl.niks (Nico Coesel) wrote: > <snip> > > > A lot can be said about Altera, but almost every hobbiest FPGA user in > > the world is using Altera devices. This certainly says something about > > the ease of use of Altera parts and software. > > <snip> > > I'd love to see your reference ;-) > Or perhaps you know most of the hobbyists personally? > > I like seeing hobbyists use the tools and parts that are best for > their activities whatever they may be. > > - John_Halmost ROTFL :) 1. all assumptions are assumed false.. well, there is some trend towards "altera-love" for the hobby use: 1) C1 reconfigurable computer -> ACEX-1K 2) japanese MSX computer -> Cyclone 3) TREX-C1 -> Cyclone so some retro-hobby folks defenetly prefer Altera, but that of course doesnt mean "almost every hobby user" Antti
Reply by ●March 14, 20082008-03-14
... ~984 hits for - Altera FPGA Hobby use - on google (no quotes). ~27,200 hits for - Xilinx FPGA Hobby use - on google (no quotes). Not that "Hobby Use" is a big line item on the financial report, but... As much as this is not a scientific survey, it is still pretty telling! Oh yes, those hobbiests are just swarming all over those Altera parts. Austin
Reply by ●March 14, 20082008-03-14
On 14 Mrz., 19:55, austin <aus...@xilinx.com> wrote:> ... > > ~984 hits for - Altera FPGA Hobby use - on google (no quotes). > > ~27,200 hits for - Xilinx FPGA Hobby use - on google (no quotes). > > Not that "Hobby Use" is a big line item on the financial report, but... > > As much as this is not a scientific survey, it is still pretty telling! > > Oh yes, those hobbiests are just swarming all over those Altera parts. > > AustinAustin, your "hit comparison" is example of bad(brilliant) use of google for statistics. the 27000 to 990 is not true ration of xilinx:hobby vs altera:hobby fact is there are no commercial retro-compurers ever built on Xilinx devices, all are Altera based, this has surprised my sometimes, as it really made me also think that hobby people (at least some) prefer Altera of course on reason for hobby-altera is the fact that LARGEST non-BGA FPGA device is made by Altera. And that latest Xilinx low cost family is not all available in non-BGA packages (i dont count the tiny S3A-50 at all, as it just so tiny) Antti