ATI's Multi-GPU Solution: CrossFire
by Anand Lal Shimpi & Derek Wilson on May 30, 2005 9:00 PM EST- Posted in
- GPUs
The Problematic South Bridge
While it's hardly talked about outside of Taiwan, ATI's South Bridge is quite buggy. The chip that is responsible for providing the motherboard's SATA and USB ports, as well as PCI slots is no where near final and many manufacturers are skeptical of ATI's ability to finish their own South Bridge in time. Note that ATI's own South Bridge does not support SATA-II or NCQ, regardless of actual bugs with the chip.
Luckily, ATI has partnered with ULi to offer working South Bridges that are compatible with ATI's CrossFire North Bridge. We've tested ULi's South Bridges and they seem to be problem-free, and our sentiments are echoed by many motherboard manufacturers who have decided to use ULi South Bridges with their ATI CrossFire motherboards.
However, ATI is pushing most of their partners to use ATI's own South Bridge despite its problems and is convinced that the problems will be sorted out in time. So a number of manufacturers at Computex are showing off CrossFire solutions with ATI's South Bridge, despite their complaints to us about the South Bridge.
At least this time around, it may be better for motherboard manufacturers to use ULi's South Bridge until ATI has had more time to get all of the kinks out of their solution. ULi's South Bridges have been in use for the past generation of ATI's chipsets, thanks to issues with ATI's South Bridges, and so far, we have not heard of any complaints.
ATI should be focused on the overall platform, not necessarily building up support for their South Bridge. Although, we do think that it is a bit embarrassing to have to turn to another chipset vendor to provide working South Bridges for your motherboard partners. It would be one thing if this were ATI's first chipset, but it most definitely is not.
Facebook
Twitter
RSS
57 Comments
View All Comments
Panndor - Monday, June 13, 2005 - link
Lets hope that this endevor by ATI doesn't end up in the same situation at the RAGE Fury Maxx they came up with. The last time they tried this they screwed it up and then cut support for the card like it never existed.Looks promising, but I could see problems if they allow different hardware to run in a combined mode as well.
Competition is good so maybe this will bring down the price of the boards and the cards now.
vision33r - Wednesday, June 1, 2005 - link
Those 2 X850XT PE cards add up to $1000+ alone while price of 6800U are going down.I think the biggest prob is not if this works or not, is if the mainboard performance is sacrificed due to the ATI north-bridge. I don't gave 90% of the time on my system, I can't sacrifice losing system performance for gaming perf.
xsilver - Wednesday, June 1, 2005 - link
what's funny is that a few months after the xfire is released, nvidia will probably announce SLI v2.0 and then everyone will talk about how that's so coolWesley Fink - Wednesday, June 1, 2005 - link
#49 & #50 - The Uli 1573 we've seen paired with Crossfire DOES suport NCQ. this was confirmed this afternoon with engineers here at Computex. The upcoming ULI 1575 southtridge supports both Sata 2 and NCQ.We also saw demos of Splinter Cell on Crossfire with the 2.0 Shader. The demos were at 1280x1024 with all eye candy enabled. Frame rates in the various demos were 118 to 120. Since we did not have reference benches for Splinter Cell, it didn't make much sense to publish these results in the launch article. What we have seen is very promising, but we need more "hands-on" benchmarking before we can say much more.
Wesley Fink
mkruer - Wednesday, June 1, 2005 - link
#51 That is the real question to be answered. My guess is that ATI will work on a SLI board and visa versa unless there is something specifically in hard coded that prevents the second slot from being used by anything other the chipsets manufactures video card, which is highly unlikely. From the BIOS and driver standpoint the MB is either has 1x16 PCIex slot or 2x8 PCIex slots.elecrzy - Tuesday, May 31, 2005 - link
its possible to have Crossfire work on the NF4/945/955. Its just that ATI won't support them through the drivers. Sigh...kmmatney - Tuesday, May 31, 2005 - link
Does the ULi southbridge have NCQ support?weblizard - Tuesday, May 31, 2005 - link
No Sata II or NCQ support. That's all I need to know to NOT want a crossfire system.bob661 - Tuesday, May 31, 2005 - link
#47I had the Abit board with the AMD chipset on it. Worked flawlessly. I gave it to a friend when I upgraded that box and it was running until last year when he upgraded his box.
sprockkets - Tuesday, May 31, 2005 - link
26# That was the 760MPX or the dual processor chipset. Don't recall any irongate issues (that was 750, 760 was the DDR version, right?)