The Phenom II X4 810 & X3 720: AMD Gets DDR3 But Doesn't Need It
by Anand Lal Shimpi on February 9, 2009 12:00 AM EST- Posted in
- CPUs
Final Words
When AMD launched the Phenom II X4 940 and 920 I called it a True Return to Competition. With the rest of the lineup now more fleshed out, it's truly a return to competition. At every price point that AMD targets, it has produced a CPU competitive to Intel's offerings.
These new CPUs from AMD are good overclockers, good performers and they don't have any real drawbacks unlike their predecessors. The most interesting CPU is the Phenom II X3 720; at $145 its only Intel competitors are the Core 2 Duo E7500 and the Core 2 Duo E8400, both of which are dual-core CPUs. The extra core in the 720 can provide a clear advantage in well threaded workloads, not to mention that it's got 1.5MB of L2 cache and 6MB of L3 cache at its disposal. In applications where the third core isn't very useful then the 720 loses its performance advantage, which I suspect will be the majority of mainstream workloads.
The DDR3 question is easily answered: wait. While DDR2 isn't an option for Core i7, on all other platforms it just makes sense simply because of the high cost of DDR3 right now. By the end of the year we won't be having this debate as DDR2/DDR3 will be at the same price, but if you're building today don't even bother looking at DDR3 unless you're building Core i7. The performance benefits aren't worth it for Phenom II, so while AM3 sounds cool, it's not necessary today. Thankfully AM3 CPUs will work in AM2+ motherboards, so you aren't forced into a relationship with DDR3 if you're not ready.
On the CPU side, what we end up with is a buyer's market with tons of choices. At the high end, if you can manage, the Core i7 is simply in a league of its own. Honestly, if I were spending close to $300 on a CPU today I'd do my best to make up for the differences in platform costs and go with an i7 over any Core 2 or Phenom II alternative.
At the low $200 price point you have the Phenom II X4 940 vs. the Core 2 Quad Q9400 once again. The 940 wins in the vast majority of cases and gets the nod at $225. The Phenom II X4 920 isn't as clear cut of a winner, as it competes with the Q8300 or the Q9400 depending on whether you want to spend slightly less or slightly more. Against the Q9400 it loses, against the Q8300 it should be a closer call. At $195 I'd call the decision torn, but I'd lean towards Intel. The same is true about the Phenom II X4 810, it actually does a lot better than I expected it would given the reduction in cache size and at $175 it is competitive with the Q8200. The strongest showing in today's introduction seems to be the Phenom II X3 720. If you do any amount of offline 3D rendering work or use any other heavily threaded apps, you'll appreciate the third core, although in most other applications the E7500/E8400 are competitive despite only being dual-core parts.
Long term this strategy can't work for AMD. Intel can make 3 E7500s in the space that AMD makes a single Phenom II X3 720; the pricing pressure is great for the consumer, but again, I'm not sure how great it is for AMD in the long run.
Other than the clear cut i7 recommendation at the high end, thanks to aggressive price cuts and competitive CPUs, you can actually have your pick of which side you want to go with here. I'd say what it really boils down to is who can deliver the best retail pricing on CPUs and motherboards. Overclockers will probably prefer the Intel route as both Phenom II and Core 2 can overclock to similar levels, but Core 2 is faster at the same clock speed. Intel does have more room to drive prices down if it should so desire and perhaps it will, although I do worry about what will happen to AMD's Phenom II strategy when Core i5 arrives later this year. While Phenom II is competitive with Core 2, remember that it's an old architecture now. Turn to the Core i7 results for where AMD will need to start looking come this fall...
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hyc - Monday, February 9, 2009 - link
I was looking for the test that justified the "DDR3 not worth it" conclusion, but didn't see it.Where did you show the results of testing the X4 910 against the X4 940, with CPU and NB clocks set identically? If you didn't test this, then how can you make any conclusion about DDR2 vs DDR3 performance on Phenom II? If I missed it, sorry for being blind.
7Enigma - Monday, February 9, 2009 - link
I'm hoping since this just went up they forgot to include a couple pages. If not, hopefully they are retesting ASAP to include data....jchan2 - Monday, February 9, 2009 - link
i'm intersted in seeing the benchmarks myself.if it's true that DDR2 vs DDR3 doesn't make much difference in performance, then what's the purpose of getting DD3?
TheFace - Monday, February 9, 2009 - link
So that when the prices DO drop later this year, they aren't caught with their pants down playing catch up on the memory compatibility front. Also, when Joe Schmoe runs to Worst Buy to replace the computer that he got 5 years ago, with a new $600 model, he can look on the box and see DDR3 which MUST be faster than DDR2.It's a selling point. In retail, ANYTHING is a selling point as long as there is a disparity in knowledge held by the parties involved.
Targon - Monday, February 9, 2009 - link
Compatibility. When Intel made the jump to DDR2, AMD waited until the prices came down on the memory. If there is no performance advantage, then the only reason to change memory types is for price reasons.For large OEMs like Dell, HP, and Gateway, it is more cost effective if all systems use the same type of memory. At this point though, since there is a price premium for DDR3 memory, just having DDR3 support on the CPU would not make an OEM add more AMD based machines to their list of systems sold.
Gary Key - Monday, February 9, 2009 - link
We are still working on the comparison, but all of the initial numbers pointed to a tie between DDR3 and DDR2 in our results so far. The BIOS releases for the AM3 boards are just now coming up to speed. I had planned on significantly more information in the overclocking section but we just received a new BIOS for the 790FX boards that allow DDR3 clocking above 1600 or so.However, at like core clock speeds, DDR2-1175 C5 is just as fast as DDR3-1600 C7 in most of the benchmarks at this point. We are running tests now at the lower end of the spectrum to show 800/1066 DDR2 vs 1066/1333 DDR3. Those results still show little if any differences.
thepiratebay - Wednesday, February 25, 2009 - link
Intel Core i7 920 Nehalem 2.66GHzin ur upper test as u can seee 2.8?????
Enoc - Tuesday, February 10, 2009 - link
DDR3 is not the problem, Deneb is bottlenecked on NB-L3 side... what it needs is NB at 2,800mhz+ with DDR3 1,600mhz+ for a good scaling...Denithor - Monday, February 9, 2009 - link
"We are still working on the comparison"SO - why would you even reference DDR3 as being useless in your title if you aren't going to provide evidence to back up this comment?
Gary Key - Monday, February 9, 2009 - link
We are still working on it but all results so far point to that being the case right now. It is difficult to have meaningful results ready when receiving BIOS releases that actually stabilize a board just a few hours before going to print. ;)