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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silverblue - Thursday, October 13, 2011 - link
And here's me thinking you were either banned or got lost on another tech site.Oh, by the way, you usually say "craps". Seems your Engrish has improved a little.
SanX - Thursday, October 13, 2011 - link
(to destroy the company).SanX - Thursday, October 13, 2011 - link
"BullShiter"grant2 - Thursday, October 13, 2011 - link
You're the tech expert writing a commercial article... so why can't *YOU* give us a judgement?gvaley - Thursday, October 13, 2011 - link
Reviewers tend to avoid extreme conclusions and in this case, it would have been an extremely conclusive conclusion.cjs150 - Thursday, October 13, 2011 - link
Just got the pricing in the UK.AMD FX-8150 is about £30 or $45 MORE expensive than the i5 2500k but £50 or $75 cheaper than i7 2600k
As Anand said BD can just about hang on to the i5 coat tails (and he is being generous). If the i5 is noticably cheaper what exactly is the point of BD?
Tchamber - Thursday, October 13, 2011 - link
I can understand ebing disappointed in the performance of bd, but when a high end gpu requires 600w, whats another 30w for a cpu? Lower is nice, but how many of us who game and have a nice cpu/gpu combo actually count the watts? Heck, when i got my first i7 920 i got the gtx285 thinking i would later run sli so i have a big psu. Now. I have a i7 970 and the same gpu and can still upgrade to whatever card i want. I tend to think multithreading is still growing, and we will see more apps use more cores, and windows 8 might utilize an fx core more efficiently. But calling bd a failure is rough, amd never said it would trounce anything, we were promised 8 cores and we sorta got them. It is an. Incremental step in the right direction, and i think the future improvements will bear out in favor of this cpu. Just like llano is doing so well in the laptop market, this could do very well in the desktop market.Bytales - Thursday, October 13, 2011 - link
We must ALSO remember the fact that windows 7 does not know of the special bulldozer architecture, and perhaps that has a role too.Once the threads are optimal allocated, perhaps performance will be a little bit better.
eagle-i - Thursday, October 13, 2011 - link
I use linux (opensuse11.4) for everyday work and would love to see if there is any difference.(linux (and other open source software) being open source is far versatile so it is in a better position to take latest cpu advantages offered by amd
I use virtualbox to run windows (in opensuse) [ cant use xen/kvm due to non vt-x/d on intel cpu -- here amd is far better they offer you the latest thereby helping accelerate its adoption]
Also, BD is a new architecture and m sure after refinement it should better AFAIK , its a right step and its now upto AMD if they can pull through with refinement.
GiSWiG - Thursday, October 13, 2011 - link
My Athlon XP 2500 (1.8GHz) overclocked to 2.5GHz stably, smacked any Intel chip. My Athlon X2 was again a nice 700MHz overclock (can't remember model number). I have an Phenom II X4 965BE. 3.4GHz and 8GB of RAM, 1300MHz @ 6-6-6-18. I'm happy with it. From sleep, Win7 is at the login prompt before my monitor wakes up. I've stopped my PC gaming days. I occasionally encode DVDs to high quality x246/mkv (~3hrs per 2hr movie) queued overnight and it is fine.AMD was a powerhouse but I've not been overly impressed since the Bartons. I'm quite happy with my setup. Really, crossfire-ing two highend AMD video cards and I'm set for any game. Gaming performance is dependent on video cards, not CPUs. I'm fine @ 100 FPS vs. 120 FPS. Your eyes will more than likely never see the difference.
AMD made a good business decision taking over ATI. They are beating Nvida in many ways, including game consoles. They allow PC gamers to have adequate motherboard/CPU/RAM combos and use the money they save for higher end video cards. Unfortunately, gamers head to Intel because they think they need they highest end CPU and RAM when they really need to sink more money into video cards.
I think AMD is stronger than most think because of the price/performance ratio. If you only had $1000 to build a gaming PC, you'll be better off spending less money on AMD CPU and more on video and still have a faster PC to spend the same ratio with an Intel setup.
I've always wish for one thing: AMD NEEDS TO ADVERTISE! Come up with a nice 6 note jingle (or 8)!