Although in his defence both WoW and AoC have made accomodations to utilize multiple cores. Not sure about other games at large, my understanding is that it's still not possible to take full advantage. (Mm, I think FSX did a patch for it too IIRC)

Quote from trebor901 :

Ive got an 8800 GTS 512MB and i get really descent frames on most games on high or max settings. I get around 300fps on LFS with not many cars and around 120 with a grid of 24. But i have got a quad core processor. Im sure if i didnt have that i'd get less fps than i do atm.

Yeah same in LFS for me. I get good frames in most things at high or max, but I can't really quite run Crysis at max - I have everything set to the "high" setting with a few on max and it's not too bad, but could be better for sure.

Quote from Jakg :

What are you using it for?

Just because it's the fastest AM2 chip doesn't mean it's the best full stop - The Proton Satria GTI puts out a mindblowing 130 (!) HP, but a Civic Type R probably puts out way more than that :P

I see your point.

I just want to play Crysis, World of Warcraft and Age of Conan. And iRacing.

I want more fps in all of the above.

I know the CPU is a tad behind by todays standards, but it's not quite a piece of shit just yet. I think I might've bought it a year ago actually.

Quote from Bob Smith :

Racing car advancemenths

Is that the study of minty airfreshers used in racecars?

Quote from Jakg :

Is the graphics card holding you back, or might it be the CPU?

That's what you're supposed to tell me!

There wasn't an AM2 chip made that was faster, it seems decent...

Quote from Jakg :

The 4850 and 4870 are getting pretty good reviews, as is the 4770 and the 4890 - what sort of performance were you looking for?

I am thinking something in the range of that 260 Core 216. Not interested in the ATi at the moment; I had a 4850 at one point and was pretty disappointed. Plus I'm not interested in switching out drivers and what not (yeah lazy I know).

I've pretty much narrowed it down to either the GTX260 or GTX275. But the 275 is $100 more, for what I am guessing is a fairly nominal improvement over the 260. The 260 is $229CAD vs $319 for the 275. Clocks are a bit higher on the 275 and it has 240 stream processors instead of ... 219 or something? Both are 896mb versions.

Do you have any idea what I should expect going from either card?

System is a socket AM2 6400+ (3.2GHz) w/ 4GB DDR2.

I run a 22" at 1680x1050, but often using component output at 1080 to the TV (never have decided if that actually affects my framerate or not).

Cheers

Quote from Luke.S :

Well if you don't need the 8800 anymore my 9800 needs a friend

I suspect the freight would be prohibitive, otherwise $50cad and it's yours

Greetings Jakg and other PC hardware gurus.

Looking to upgrade said video card, need some proper advice on what would be worth it. Not looking to spend $600 or anything though either. I did read breifly somewhere that the GTX260 (Core 16, whatever the hell that means) would be a significant upgrade for a mid range price. Is that correct or has that card been succeeded already?

Thanks for your help!

Only on tires that get twice as hot.

Idiot!

Quote from Shotglass :

however thats hardly relevant since what eg genesis has to say is not that the universe formed in 6 days but that it was created by some supreme being

ex-freaking-sactly.

As a Christian, I get very annoyed that some of my fellow Christians think "God made the universe in 6 days" literally :doh:

Hard to do when one day is based around things that He hadn't created yet, furthermore time being a part of creation itself (IMO of course).

Quote from DragonCommando :

I have never seen a stock turbo push more than 10psi and do it without dropoff. If auto makers are running the turbos to the point of drop off they can't be very well matched turbo chargers.

It seems like you just said two different things?

I'll assume your first sentence was meant to actually convey that you've never seen some pressure loss at high RPMs on a stock vehicle, and also never seen a stock vehicle push more than 10lbs - correct?

Quote :

If they intend it to do 12psi and it doesn't stay there to redline there is something wrong. That turbo is running above its intended max speed.

Not really, it just means that the turbocharger they used has an efficiency range more suited to lower engine speeds for the engine it's mated to. I have no experience w/ the Saab, but the SRT-4 engine is just a torque beast. The torque curve is basically flat for a wide range of RPM and it has serious torque at low revs for a 4cyl. The compromise is that there is some pressure loss at the top of the rev range. They could, instead, allow higher pressure than they do and deal with a greater % of pressure loss as engine speed climbs. I'd have to double check, but I think that part of one of the OEM upgrade packages does just that as part of the package.

Don't forget that engine speed is climbing, not staying constant. It's possible that given enough load to stop the engine from increasing in speed, the compressor might flow enough air to fully pressurize the manifold - at least that's probably true at the point where it first starts to lose pressure. The impeller won't just continue to push more and more air at the same increasing rate indefinitely.

Last edited by Ball Bearing Turbo, Thu 21 May 2009, 19:33.

Quote from Matrixi :

Catch my drift?

LOL Good one

Quote from Feffe85 :

The Saab 9-5 2.3T has a max boost of 0.8bar stock

Yeah, and the original Dodge SRT-4 was around the same. and would hold that pressure from around 2K to 4.8K, with a slight drop from there to redline.

Quote from Vain :

@BBT: What you likely mean is that the geometry of the impeller is optimized for a specific ratio of gas velocity to impeller speed so the impeller blades are hit by the exhaust gasses head-on for maximum efficiency. Is that right?

Well, I was specifically talking about the impeller side not the turbine side. The turbine side works much less through kinetic transfer simply based on exhaust flow rate than it does allowing the exhaust to expand through the housing. That is primarily where the energy is dumped into the turbine; thus the pressure differential across the exhaust turbine is the primary determining factor of how much energy is put into it.

Quote :

but beyond 5.5k rpm the impeller (you mean turbine) would mostly stop converting energy from the exhaust gasses to the propeller but rather act as a block in the exhaust system because it's geometry doesn't at all fit the current situation (in this situation it'd only move due to it's friction against the exhaust gasses, not by expanding the hot gas).

Ah yes I see what you're saying now, sorry, that's basically right. But in my post I was speaking soley for the compressor (impeller) side of things. Obviously everything has to match properly - the flow characteristics of both sides of the engine have to match both sides of the turbocharger to acheive what you want out of it.

Quote :

On the other hand I could use an impeller that works at a high efficiency at 7k rpm, but I wouldn't be able to get the turbocharger to rotate very much before 5k rpm.

Is that train of thought correct?

As a generality yes, if I understand what you're saying.

Quote from jaxx751 :

I does cool down, but only after a good bit of driving. anyone who has done a enduro knows what I'm talking about. After lot of laps you have to work hard to keep the tires warm.

Yeah Glenn had me really pondering there for a bit...

But I think that means that his idea that you quoted is even more right; since less "core" material makes it more difficult to maintain temps in LFS. The molecular activity should remain relatively the same despite how much tread is left, but since heat dissipates more rapidly when there is less tread in LFS that would indicate that much of the core temp is related to therodynamic transfer from & to the surface rather than hystereis.

That or I've consumed too much Guinness; either of which is entirely possible. And it's only Wednesday, just imagine Friday.

Heh, that's actually a very awesome post.

Quote from Vain :

@Simpson:
I assume you attribute the loss of turbo pressure at large rpms to the upper limit of turbine speed due to friction? High engine speed means large a amount of air is sucked in, but at high turbine speeds the turbo generates a lot of friction which may disable it from providing the engine with enough fresh air to maintain maximum boost pressure. Am I understanding this correctly?
Vain

Quote :

Not quite that.
Turbo dont generate much friction, because it would killed itself quickly (its revs to 110-150k rpm!!)
The reason why preasure drops is because cold side of the turbo cant create such presure (push such high mass of air) engine would suck. If it could it would be almost "perpetum mobile".

Yeah this is right; but to answer that more in depth for Vain: turbines have a narrow efficiency range where they pump well. In essense they are really one-speed devices, and you need to match the efficiency range on the impeller with the demands of the engine. So the turbo that works well from idle to 4K typically "runs out of breath" because it's already past it's efficiency range while delivering enough boost to be usable lower in the engine's rev range. IE; the impeller like to be at certain RPM to pump well, and that particular rate cannot match (with old school systems anyway) every situation the engine encounters.

Quote from Becky Rose :

I have come to expect your comments to be a bit more thoroughly considered than that hun.

LOL, fair enough.

I'd be happy to post some well thought out drivel but in fact I spent about 50% of the forum's bandwidth last time I did so, and I'm not feeling the energy to do it again. Besides, last time Maggot got upset and left and I can't have a fellow Canadian becoming irate once more . If you're interested in my lengthy blatherings and missed them last time you can find them here:
http://www.lfsforum.net/showthread.php?t=23515 (you'd have to read the entire thread all the way through to see what I actually have to say, see you in two weeks)

I'm happy to let everyone carry on with their bawhawing this time.

Last edited by Ball Bearing Turbo, Wed 20 May 2009, 19:39.

Really? That's your whole motivation? I'm honored!

Quote from S14 DRIFT :

It's much easier to say "basically cut slicks" than to say "high performance trackday spec tyres that are designed to be used hard and stay consistent at higher temperature ranges while still remaining legal for road use and having a half arse attempt in the cold and the wet.

So then you're just lazy, and by extention horribly inaccurate. The former means nothing like the latter.

Then you get on a tirade because you say ignorant things but it's never "what you really mean". Spend more time thinking, and less posting, and maybe you'll have a productive conversation someday. Verbosity for the sake of it is nothing more than handwaving.

Quote from S14 DRIFT :

Seriously BBT, grow the **** up and if you have a problem with me, add me to your ignore list because you're becoming nothing more than a troll..

No way, your dodgy snotgobbler rants provide me a great deal of amusement - I don't want to miss out on that

Quote :

I was talking about tread, or rather the lack of it, when I was saying "what are basically cut slicks"

Nah I call bullshit and backpedaling at an incredible rate. I must issue credit where it's due though, you're the most glib fellow I've ever seen on the forum. See, you said it in the context of why the tire got chewed up... unless you really think it was because of it's tread pattern (in which case you're stupid, not just lying)

Quote from S14 DRIFT :

To be fair all of those cars are fitted with high performance tyres, and in most cases what are basically cut slicks..

:rolleyes:

Quote from yeager :

Actually i've not seen a slick race tyre that is comparable in design to a road tyre. There are obvious similarities between a race wet/intermediate tyre and road tyres simply because techniques in tread pattern often migrate from race to road. However thats where the comparison stops because even though they may look similar, their construction and materials are different.

Don't bother he was trying to pretend he didn't say something blatantly stupid and make it look like he "didn't say what he meant". He said "high performance tires were basically cut slicks", you pointed out he's flat out wrong, and now he's trying to save face... again, like in almost every other thread I've been reading lately.

Oh boy! A scientific 'discovery' :hyper:

So awesome, science has never been wrong or mislead about anything, ever in history. I in fact am 100% confident that everything we know and can measure today is the end-all, be-all of existance, period. For such powerful and "intelligent" beings us humans are, I am surprized we can't stop wee little organisms from killings us however .

Quote from Rotareneg :

I'm not looking at the speedometer, I'm looking at the tachometer.

Heh, well then that makes even more sense because the phenomenon is the same and given gear reduction shows less of an error percentage wise. Same principle to gauge needle acceration applies anyway of course.

Quote :

And in real life tires do not slide constantly when driving straight on pavement. The rubber in the contact patch does not move relative to the road surface except where it deforms to conform to the road surface at the front edge and then begins to return to it's normal curve at the rear.

When under power or braking there is a slip ratio relative to the surface. Just because you don't perceive it, doesn't mean it's not there. Read up on tires.

Quote :

Even when turning the contact patch will remain static to the surface with just more scrubbing at the edges, at least until the point where the turn or acceleration (or both) causes the contact patch to start sliding and/or become so deformed that no point is static any more.

No, there is no transition from static friction to dynamic friction on a tire in motion. As long as there is a torque on the tire (longitudinal accel) there is a slip ratio occuring.

Quote from Rotareneg :

One thing I've always noticed in all driving simulations (LFS included) is that the tires are always slipping. Take a UF1 with the default config up to 60 mph and quickly bounce the throttle open and shut. In LFS the engine speed rapidly jumps up and down a little bit as the ever-present amout of wheel spin reacts to the different amounts of torque.

Yes and this is technically correct behaviour. It shows however that the speedo needle updating isn't slightly latent even for small changes like it is in real life. Before LFS took speed display from the axle speed, it was not like that, but now that it does (that was changed a couple years ago) you can see this phenomenon. In the very first patch it was released, there was basically zero buffer on the speedo - it literally read exactly what the wheels were doing at any point in time and it looked strange. It needed to be limited in rate of travel in terms of max degrees per second, and have some latency. There is likely not enough latency on tiny changes yet - it seems this nuance isn't noted by most developers.

You'll find that wheels under power are not actually revolving at a speed that matches the actual road speed; there is a small discrepancy there because of the way tires actually work. Real tires are, in fact, in a constant state of slip when you're in motion, it's just a matter of how much.

Quote from boosterfire :

Yes, some could have broken belts and make a very, very loud squeaking noise.

ROFL!

But, the OP has a pretty good idea there.

Taking it a step further, the LFS sound engine could be made to have some constant random variation in some of the many variables that already exist in the SHIFT-A interface. Thus, when you set it to a certain value, it's actually saying "value of 40 +/- 15" or some such, and the sound engine could randomize the setting within that range at some sort of interval; a relatively quick one - not like every few seconds so you get a discernable change in particular instant. Messing around with that idea could alleviate some of the monotony in the engine sounds.