The Bulldozer Review: AMD FX-8150 Tested
by Anand Lal Shimpi on October 12, 2011 1:27 AM ESTCache and Memory Performance
I mentioned earlier that cache latencies are higher in order to accommodate the larger caches (8MB L2 + 8MB L3) as well as the high frequency design. We turned to our old friend cachemem to measure these latencies in clocks:
| Cache/Memory Latency Comparison | ||||||
| L1 | L2 | L3 | Main Memory | |||
| AMD FX-8150 (3.6GHz) | 4 | 21 | 65 | 195 | ||
| AMD Phenom II X4 975 BE (3.6GHz) | 3 | 15 | 59 | 182 | ||
| AMD Phenom II X6 1100T (3.3GHz) | 3 | 14 | 55 | 157 | ||
| Intel Core i5 2500K (3.3GHz) | 4 | 11 | 25 | 148 | ||
Cache latencies are up significantly across the board, which is to be expected given the increase in pipeline depth as well as cache size. But is Bulldozer able to overcome the increase through higher clocks? To find out we have to convert latency in clocks to latency in nanoseconds:
We disable turbo in order to get predictable clock speeds, which lets us accurately calculate memory latency in ns. The FX-8150 at 3.6GHz has a longer trip down memory lane than its predecessor, also at 3.6GHz. The higher latency caches play a role in this as they are necessary to help drive AMD's frequency up. What happens if we turn turbo on and peg the FX-8150 at 3.9GHz? Memory latency goes down. Bulldozer still isn't able to get to main memory as quickly as Sandy Bridge, but thanks to Turbo Core it's able to do so better than the outgoing Phenom II.
L3 access latency is effectively a wash compared to the Phenom II thanks to the higher clock speeds enabled by Turbo Core. Latencies haven't really improved though, and Bulldozer has a long way to go before it reaches Sandy Bridge access latencies.
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HW_mee - Wednesday, October 12, 2011 - link
I did not expect Bulldozer to rock the CPU world, but....A Bulldozer has a 256 bit shared FPU which is capable of calculating 2x128 bit FP instructions at the same time vs 128 bit FPU per core in Phenom II
Bulldozer 8150 should be able to process 4x256 bit FP instructions or 8x128 bit FP instructions at a time, while Phenom II 1100T should be able to process 6x128 bit FP instructions at a time.
The short calculation above shows Bulldozer should have an advantage over Phenom II in FPU heavy computations.
The test don't lie and the two processors perform the same, but there should have been a difference, in theory.
HW_mee - Wednesday, October 12, 2011 - link
Need that EDIT button.... Bulldozer has a 256 bit shared FPU per module, which ...
Mr Alpha - Wednesday, October 12, 2011 - link
I believe Carmack mentioned during QuakeCon that the textures are compressed using Microsoft's HD Photo (aka Windows Media Photo).Ryan Smith - Wednesday, October 12, 2011 - link
Aha, I thought it was something like that, but I couldn't come up with the right keyword. Fixed. Thanks!IceDread - Wednesday, October 12, 2011 - link
This is an utter failure from Amd. For a personal workstation or home computer there is simply no reason to choose Amd over Intel. There are even cases when the older Amd cpu is better, which to me looks insane.So we get nearly no new price pressure on the market from this ether. It's just like a silent release, the market wont notice and the customers wont notice that there is a new Amd cpu on the market because the cpu has nothing of interest it can offer. This is really disappointing.
cjs150 - Wednesday, October 12, 2011 - link
You have summed it up well.Worse performance, crap power consumption. Only way to save this is a big price cut say to $150-160.
The AMD approved water cooling system looks to be a gimmick, and I say this as someone who prefers water over air cooling. I do not see the point of CPU only watercooling - if that is all you want then air cooling is cheaper, almost as good and a heck of lot easier to install. IMO CPU+GPU is the minimum if you want to watercool, unless you are into overclocking when a single rad is too small
I guess AMD are rapidly becoming a niche player because as bad as BD is, intel's atom is worse compared to the AMD equivalent
IceDread - Wednesday, October 12, 2011 - link
A very high price cut could save the product like you say but that might mean Amd will lose cash, thou it's not like they wont lose cash already being so far behind. I really do not see a place for this new cpu.This is bad thou, because we need competition on the market because otherwise Intel will only have to take customers willingness to pay a certain amount of cash for a cpu into account, there is no competition.
I like water cooling thou, but that is because I like to overclock some. Water cooling systems can also be more quite but not necessarily. Most people I do not believe will gain on a water cooling system, that would only increase the price of the product.
haplo602 - Wednesday, October 12, 2011 - link
yes there is. socker F and 2389 optys. they are dirt cheap right now :-) if you can get a mobo that supports 2439s then you are golden.g101 - Wednesday, October 12, 2011 - link
I swear, you fucking kids are ridiculously stupid. Those of us that actually use CPU's to their full potential understand that this is far from a 'failure'. You gamer children haven't got a clue what 'future proofed' means.IceDread - Thursday, October 13, 2011 - link
Hey retard, there is no smooth way to utilize this cpu. Trty and realize that.There are few cases where strong cpu's are needed, servers, graphics, data processing and gaming. Most readers on this forum is probably gamers and thus writes from that perspective. Is that so hard to understand.
From my point of view as a solution developer of funds and insurance systems this cpu is not of interest because the alternatives for the servers are better and for client computers the need of a strong cpu is not of interest at all usually and thus this cpu is not of interest there ether.