Looking at specs, the Q8200 and Q8200 run at the same exact speed and have the same exact amount of cache.

The Q8200S was probably just a higher quality core that they binned for lower power devices.

As far as LGA775 goes, you start seeing real performance around 450 fsb.

480fsb is really nice when running DDR 2 at 1:1 for an effective RAM speed of 960.

The boards that work with DDR3 and are great overclockers should see even higher performance.

As far as most games on XP, the much higher clocked E8500 (both clock speed and fsb speed) as well as the higher amount of cache, is going to net you higher performance unless overclocking the slower speed CPUs.

Thanks a lot for your input, the E8400 was my initial choice as well. The board is 800/1066/1333 FSB speeds, I have planned to buy two 2 GB DDR2 800MHz modules (they still have them brand new on the shelf). The board has two DDR3 slots next to the DDR2s, though I think DDR3s are 8GB min, and the board only accepts 4Gbs of DDR3 total. Anyways, the difference in the memory performance is negligible here, I'm more concerned about the temperature and longevity.

E5800 is a Pentium dual core, 3.2GHz, 800FSB with 2MB cache
E8400 is a Core 2 Duo, 3GHz, 1333FSB with 6MB cache
Q8200S is Core 2 Quad, 2.33GHz, 1333DSB with 2x 2MB cache
XP and XP software is generally not heavily multithreaded, XP being the first "home" OS to support it, so a higher clocked dual is likely to outperform a lower clocked quad.
I'd take the extra cache and FSB of the E8400 over 200 more MHz of the E5800 though.
RAM? DDR3 comes in 1 or 2GB as well, at very low prices if you can find them as they are so out favour compared to 4's and 8's, they are what people take out when upgrading later DDR3 platforms. I would choose to run DDR3 at 1333 (even though it's by OC, also 1600MHz DDR3 can generally drop to 1333), For the DDR2, I would set is a 667MHz as dual channel 667 fills a 1333 FSB in traditional quad pumped style (like the old dual DDR400 on early 800FSB)

Thank you Matth79, it is indeed very trustworthy and informative to hear good advice from good people. So the E8400 it is, and will look harder for the two matching 2Gb DDR3s at 1333 then.

I second the notion about the best dual you can find.

Single threaded performance is what will make the greatest impact here.

There’s no such thing as 50% more efficiency in the same generation; if it draws less power it generally also does less work.

I was at a similar point where I had this nearly maxed out Core 2 Duo system (Mobile on Desktop) and was considering the exotic Quad core upgrade. But figured that if I really needed such multi-core performance from such, I should just swap the whole motherboard and go Sandy/Ivy Bridge generation of hardware, which actually boosts single-core responsiveness as well.

^In the Hackintosh scene the Core 2 Duo used to be very popular,though
because it was very compatible with OS X 10.4/10.5/10.6 and up (no CPU software hack needed).
Here, it sometimes made sense to use an quad core such as, say, Q6600 to improve performance.
It helped reducing compiling time when using MacPorts, for example.
From my own experience, that stuff easily causes all the CPU cores to peak at 100%.. 😵
I'm not much of a gamer, though, so I'm speaking under correction.

On the desktop, compiling something with make -j or rendering opengl graphics via llvmpipe can utilize lots of cores. Otherwise it's mainly multi user server workloads that can load many cpu's at once. The games of 20 years ago do just fine with two fast cores.

Halofiber86 wrote on Yesterday, 17:18:

This is in the software section, because I know the hardware will fit, but it's the Windows XP 32 that:
1) may only utilize 1-2 cores, why waste a Quad then?
2) can hardly tell me, which one is performing better (Max Payne 3 will be quite mediocre with any of the three).

3) waste of the extra 32 bits too 😀

actually, for practical use 775 is often very cheap and really doesn't need top end components to be fast with XP anyway. Some games benefit from faster Ghz so go with that. What i'd find interesting if there is any game that worked on 32 bit XP that is going to be faster on a 2 core 775 than the same game atop vista or w7. I mean in actual experience terms, rather than some marginal fps difference. I suppose there is, but i never found an early to late 2000's game that wont run on W7 on specs similar to later 775 with a modest graphics card that isn't just fine (and hence never makes me think i need XP to get better play experience)

I like XP though, just finding myself not using it much for games

Windows XP was also very good for 2D performance, since it was 2.5D based rather than 3D (Vista/7).

On XP, DirectDraw could access physical frame buffer for overlay video, for example.
It also did have full GDI acceleration and was able to draw GDI+ natively.

In Windows Vista, with its WDM 1.0 driver model, this was gone.
Windows 7 brought back partial 2D/GDI acceleration, though.
If using WDM 1.1 or higher compliant device drivers.

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