Q8400/Q9400 for PCSX2

[cal_guy]

Intel CPUs in general seem to outperform their AMD equivalents on the emulator, even when both are using SSE2.

It's important to distinguish the older K8 type processor with the post Barcelona type Phenon/Phenon II/Athlon II processors which have significant improvements. Most notable (for PCSX2) is the ability to process a 128-bit SSE instruction in a single cycle rather than two cycles found in older CPU(something that the Core 2 series also introduced).

[Chris8282]

I don't overclock. Each computer I buy I want to last as long as it can since I will always use it. So, at stock speeds, are they equal?

[KrazyTrumpeter05]

Probably, though clock speed still counts for a lot. When building a PC primarily for PCSX2, I pretty much always recommend Intel over AMD, especially an Intel processor with the SSE4.1 instruction set. If you get a good cooler, overclocking won't really shorten the life of your processor. Processors die early because of poor cooling, and sometimes with super high voltages(only needed for EXTREME overclocks). An overclock to 3.4 ghz would be fairly modest with that processor honestly, something easily handled by a good 30-40 dollar CPU cooler.

[Chris8282]

Again, at stock speeds ... Any comments?

[Air]

I suspect the Q840 will win over the AMD for PCSX2 only. I make no assumptions regarding any other application or game. All PCSX2 active developers own either modern Core2/i7 cpus, or out-dated AMD cpus. No one owns a phenom, and from what I've read in chat, none of us plan to get a Phenom anytime soon. Specifically it means that we're going to tend to favor Intel when we optimize. So unless the Phenom was heads and shoulders above the C2Q in performance (which it's not), it's going to have a disadvantage in PCSX2.

Furthermore, the AMD cpus do have a much smaller L2 cache. And while going from 4MB->6MB L2 hardly matters for anything anyone cares about (large server-size databases and 7zip compression benchmarks probably aren't high on your "i care?" list), going from 2MB->4MB does matter. To make matters worse, AMD's multi-core L2 sharing technology isn't anywhere near as good as Intel's, so that 2MB ends up feeling like a lot less than the same 2MB would on a C2Q. I'd say that's one of the primary reasons for the Phenom X4's performing poorly on PCSX2.

[Air]

Additionally, the Q8400/9400s run at like 40% less power and 25% less temp than the Phenom x4 945. So if you're concerned with the idea of having hardware that's stable, sturdy, and tending to last a long time (which you've hinted at), the Q8400 is a clear winner over the Phenom x4 945 on that front.

[Chris8282]

Wow, that was amazingly useful, Air. You're always so very helpful. Thanks man!

In addtion to everything you've said, a Core 2 Quad build is about 120$ cheaper with the price drop that happened about 4-6 days ago. So, I'd say it's just become a no brainer

[Lamarr]

Thanks a lot, Air, that sure makes me feel better about my new Q9400. Works really well, by the way, perfect 60 fps in SMT: Nocturne. So me, I recommend the Q9400, especially since I heard you can easily overclock it to 3ghz per core. Gotta try that sometime soon.

[Edit]: Jesus Christ, 102 FPS with no Frame Limiting! This is seriously amazing. Looks like I can finally scrap my old PS2!

[Chris8282]

Why do you recommend the Q9400 over the Q8400?

[Air]

I personally went with the Q9400, though I did so because it happened to be on sale and with rebates was actually cheaper than the Q8400 at that particular moment in time.

But for overclocking both chips should end up being about the same, since they're apparently the same fabrication process. For what it's worth, I've pushed mine to 3.4ghz stable, running below 50c temps under heavy load. But I don't like the idea of wearing my hardware thin either, so I usually run at 3.2ghz; which runs stable with only a minor bump in voltages.