Bizarre minimum CPU requirement, read if you have a sempron 64

[DexterCarlisle]

Okay, so the motherboard of my old computer, an Athlon XP 3000+, 1 gig PC3200 RAM, and an unlocked eVGA Geforce 6800 (unlocked all pipes, so like 6800 GT with only 128 MB memory), on which I usually ran BF2 on medium with no probs, except on huge servers, dies.
I buy a new AM2 mobo, and get a sempron 64 2800+, 1 gig PC6400 RAM, and an x800 GTO card. Based on the card and my previous experience, I figure I can run the game at the same settings, if not higher.
NOPE.
I try high. 15-20 fps.
I try medium. 15-20 fps.
I try low, with 800x600. 15-20 fps. Standing in a corner on the carrier on Wake Island.
This blows.
I uninstall BF2, defrag, reinstall BF2, defrag.
No difference.
I update all drivers.
No difference.
You get the point.
I read all these articles saying that games, including BF2, really don't rely on CPU that much. I see charts showing maybe a 25% reduction in performance by changing the CPU. But this is the only thing on the new setup that is weaker than the old setup.
I also read that 2800+ semprons are sweet overclockers. People hitting 2.2GHz or more on stock cooling (it's 1.6 GHz as is). So I do this. No problem getting up to 2 GHz on stock, at 1.4V, which also means I get to use my PC6400 memory at full speed. Temps at max load reaching 38*C. Definitely a good buy for fifty bucks at NewEgg.
I'm expecting at most a 25% improvement, since I increased the clock 25%.
I now get 40-60 fps on medium, 1024x768. SWEET!
I just want to know what's going on here. Is there some crazy ultra-bottleneck going on, where if you drop the CPU below a certain speed (e.g. 1.6 GHz) you get a bunch of tasks normally taken by the CPU processed instead by the graphics card, or what?
I'm not complaining, but I'm very curious what's happening.

[donnien8]

Re: Bizarre minimum CPU requirement, read if you have a sempron 64

that sucks

[imported_Jazza]

Re: Bizarre minimum CPU requirement, read if you have a sempron 64

The CPU can't process the other 63 people running around.

[DexterCarlisle]

Re: Bizarre minimum CPU requirement, read if you have a sempron 64

If I get bored one day, I may try to carefully test this, by dropping my processor speed from it's current (O/C'd) state down even further than stock, and see how this correlates with FPS. It seems counter-intuitive that a 25% increase in processor speed causes a doubling-to-quadrupling of performance. Any engineering wonks want to explain that?

[coolbho3000]

Re: Bizarre minimum CPU requirement, read if you have a sempron 64

That's funny, my P4 3.0Ghz can "process 64 players" easily.

[DexterCarlisle]

Re: Bizarre minimum CPU requirement, read if you have a sempron 64

Uh oh, is this gonna become an "AMD vs. Intel" thread? Or just a "you bought a sempron, retard, what did you expect" thread?

[GeoffRowley]

Re: Bizarre minimum CPU requirement, read if you have a sempron 64

The semperon was a downgrade, or am I wrong? You should have expected less performance, mayeb not this much less, but why buy a better mobo, and then buy a worse cpu

[BIFF EXPLODER]

Re: Bizarre minimum CPU requirement, read if you have a sempron 64

i find it quite weird aswell why did u make such a big downgrade :S

[mlkmnz]

Re: Bizarre minimum CPU requirement, read if you have a sempron 64

i find it quite weird aswell why did u make such a big downgrade :S

Money probably. Then again when building a gaming rig your cash is better spend on the graphics card first, which it looks like he's done.

I find his performance gain by overclocking to be pretty interesting actually, in all my tinkering CPU speed bumps of up to 30% have done next to nothing to game performance in BF2.

[DexterCarlisle]

Re: Bizarre minimum CPU requirement, read if you have a sempron 64

mlkmnz hit the nail on the head. MONEY!
I guess it wasn't that much difference between the sempron 64 ($50) and the cheapest athlon 64 AM2 socket ($85), but that money went to the card. Besides, I had read all these articles showing relatively little effect of the CPU, which I misinterpreted to mean including the semprons. But I guess they are just too weak at stock. Fortunately they're cake to O/C, which gave me the bizarre several hundred percent performance gain on a 25% frequency increase, thus leaving nothing to blame for my weak scores but myself. It wouldn't have anything to do with my memory being allowed to run at full DDR2 800 speeds (semprons are built to only work up to DDR2 667 at 200MHz HTT, from what I understand).
I'll probably not overclock the processor any more, until BF2142 comes out and I need more performance again, or the athlon 64 prices drop and I can afford to fry the poor sempie.