Howdy.

When open tracks first came out I noticed lots of people had problems but I was unaffected - my fps dropped quite a bit but LFS was always driveable even with a full grid on open layouts. (My PC is old - E4300/1.8GHz, Radeon X1650.)

I recently upgraded to 0.6E (from C), which may or may not be relevant, but in the last week or two while practicing for a race on AS6X/A61 I've found that even when alone on the race server, I am intermittently getting jerkiness and low fps which is bad enough to cause me to crash - frame rate drops to 15 fps and below, but the main issue is probably the jerks.

Nothing else on the PC seems to be consuming cycles (I've closed more or less everything else.)

Searching this forum didn't show up too many hits (surprisingly), so I'm wondering if anyone can help:

Firstly, is this mainly a GPU or CPU thing?
Secondly, any recommendations to mitigate it?

I haven't tried changing much yet, partly because it's so intermittent that I'm not sure how to conduct sensible tests. (I can drive 10 laps and only one of the laps hits a problem, which is normally at a particular part of the track. And the laps are LOOOOONG! )

Help gratefully received!

Quote from Neilser :

(My PC is old - E4300/1.8GHz, Radeon X1650.)

ancient history is what you call that.

but for the open layout thing. I think it's your whole system. The reason it's lower than normal is because everything gets older, and also slower over time.

for an upgrade you have 2 choices.
1- AMD/ATI
2- INTEL/NVIDEA

number 1 is cheaper and gets you better price/quality
number 2 is more expensive but also better with heat/power usage

Just wondering,which part of track is it? The AWS layout has quite big amount of objects,wondering if they are causing fps drops. Or is it when your car turns in direction where the most of the track is in front of you?

XFG, BL1, Full screen, 1 car, no layout, on start grid, no OC

this is what I get


There is always some difference in FPS, altough I don't see much reason for FPS drop.

Quote from Eclipsed :

Just wondering,which part of track is it? The AWS layout has quite big amount of objects,wondering if they are causing fps drops. Or is it when your car turns in direction where the most of the track is in front of you?

It's a chunk which starts about half-way through sector 3, roughly the 5 or 6 corners before the hairpin, most noticeable on the fast left handers.

I did wonder about objects and view direction being important, which might conceivably change from lap to lap if the angle the car points is subtly different, but it's so hard to repeat...

Edit: clearing the layout boosts the FPS by about 30%; without a long test I don't know if it would prevent the jerkiness. I also know why you added so many objects - anti-cut )

(And yup, CodeLyoko1, it's ancient. If money was no object, I'd replace it tomorrow!)

Quote from DANIEL-CRO :

OS BL1 BL1X
Win7 106 89
WinXP 134 95

Bizarre that Win7 is so much slower than WinXP. My drops are MUCH bigger than yours. The FPS in AS6 is 93, while in AS6X it's 34 (fine until the jerks occur). The CPU usage goes from 15% to 50% (i.e. one core is flat out) when I switch to open layout (which suggests that GPU tweaks may not help...)

PS: thanks for the help guys

Update: I can't understand this at all, but today in the actual race, I had 70-90 fps ALL the time. I then went back to single-player mode just now to see if that was still going down to 30ish fps and it was also 70-90 fps, with the same layout as before on AS6X. I don't think any options were changed in between (I tweaked a few here and there but put 'em all back, and in any case I really think it was the CPU which was pegged anyway, not the GPU).

I'm totally bewildered now...