Monday, August 22, 2011

New Zambezi leaks from Far East

Check this out:
http://diybbs.zol.com.cn/11/11_100430.html <- supposedly 4C 3.9Ghz Zambezi (with power limit removed?)



Same thread page six:
http://diybbs.zol.com.cn/11/11_100430_6.html
8C 2.8Ghz ,A1 revision?? So the samples seem to work fine(bug-wise) but have been power limited to stay within certain power cap.

Quote from the guy who posted this:
8-core results here

Bulldozer and then check the performance of eight threads can not pay would in 9000, the main reason for the test problems is power supply and motherboard BIOS issue, bulldozers high demand for power, and now the BIOS only 60-70% of shipments performance only.


The logic above is the following: first silicon revisions (A1,B0,B1,B2?) were functioning performance-wise (mostly) as simulations predicted BUT they were very leaky and were gobbling power like crazy.So in order to validate the platform,AMD has used the new feature in Bulldozer design called "power cap" in order to limit the power draw of the CPU and still make it work on latest 900 and 800 series AM3+ boards (check the official Bulldozer blog about this useful feature in Interlagos variant ). The effect of this was that those early Bulldozer samples were throttling down aggressively (voltage and frequency wise) in order to stay within the spec. This resulted in much lower clocks then what applications like CPU-z reported- in the range of 60-70% of specification.Turbo functionality was impaired also.
After the platform is validated, AMD was already producing the B3(C0?) which supposedly has the leakage/power draw problems fixed and clock target was being met within the 95/125W specs( say 3.6Ghz 8150 8C is now hitting all targeted specifications,Turbo included,all within 125W -unlike the early A1/B0/B1 which were gobbling power like crazy with poorer yields). So after all things said,retail will perform 40-60% better than what the latest leak from chiphell showed and what the two images above (kinda) illustrate-if they are genuine that is.

As for the numbers for both 4C and 8C they kinda confirm it's possible. 4C 3.9Ghz allegedly gets 18.9K,8C 2.8Ghz allegedly gets 23K. Scaling is probably not perfect going from 4C to 8C ( i assume around 1.7x,software and hardware limitations):
18.9K / 3.9 x 2.8 x 1.7 =23K. So the scores kinda align. But the problem is that scores are roughly 1.9x higher per core than Phenom... I can't see from where this speedup comes. So take with salt

1 comment:

  1. Another photoshopped fake http://forums.anandtech.com/showpost.php?p=32167167&postcount=1143

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