AMD's Bobcat and Bulldozer

[Sn0wm@n]

savantu is starting to post more .. and we get less terrace .... we get more terrace if savantu post less ... anyone has a theory as to why ???

<totally rhetorical question, NOT real numbers>
Which would you rather have:
80% of the performance with 50% of the cost and 50% of the power consumption
100% of the performance with 120% of the cost and 120% of the power consumption
</end rhetorical question>

People keep seeing that 80% number and thinking that it is a compromise. What they don't understand is that by sharing components we are able to add more cores in the same die space and same power budget.

It is by no means 80% of today's performance.

good to know

so to terrace and savantu ... i think its clear that BD will be more powerfull than K10.5

[madcho]

I've made some calc about BD, it's my own calc so it's pure speculation, nothing real, but it's awesome.

i used Magny cour 2.2ghz 12 cores for base and used the +50% +33% more core, i used 7.95x speed up for cinebench 11.5 for 2P 2x6 cores opterons.

And used the 80% from AMD slide to calc the multithread speed up of BD.

So if my calc are not f*cked ( i hope so ), i get :

16 cores ( 2x8 on G34 or 2*4 modules ) with 8.48x multithread speed up.

I set the IPC to magny cour to 1. So P1 ( P in single thread ) is 2200*1=2200, and P2 ( P in multithread ) is 2200*1*7.95=17.490k

+50% perf for BD in multithread it's said.

so : 17.490*1.5 = 26.235k.

So P1 for BD is 26.235k/8.48=3093.75.

So P1 BD / P1 magny cour = performance improvement for BD = 3093.75/2200=1.40.

So we know P = F * IPC, and we the deeper pipeline target 20 to 25% frequency improvement.

With 20% we get 2640mhz, so i use 2.6ghz for more rationnal number.

Aproximation IPC is P/F=3093.63/2600=1.189 to compare to 1 taked for magny cour.

SO I GUESS I'M CRAZY TO DO SOME STUPID CALCS LIKE THAT BUT I DON'T WANT GO TO ASYLUM ... TY