How to tell when bottleneck exist?

So first of all here's my setup,

E8400 @ 3.6Ghz 400MHz x 9 1.32v
EVGA 780i
2 x 2Gb Kingston HyperX DDR2 800 CL5
2 x Asus 9600GT 512 unclocked

I'm still a newbie in overclocking, in fact, the only reason I started overclocking was because the bottleneck issue I've had with my stock E8400 when playing games. Now at 3.6Ghz I've gained a noticeable FPS and performance, 3Dmark06 score 15969.

I'm wondering how could I tell at what speed I should run my CPU that's best match my 2 9600GTs performance? I know if I want to push my CPU further I most likely will have to overclock my ram as well. I'm also looking at upgrading to the new i7 but still I want to try get the most out of my current system

Sorry but I've got another question, if I do end up getting a new i7 system, is it worth running SLI? Say 2 x GTX285? Or is it better to just get a single GTX295?

Thank you in advance.

If you're just gaming I wouldn't suggest the i7. 2 cores is plenty for gaming. What exactly do you do other than game? If you do other things that could use the 4 cores, then i7 would be sweet.

I missed the while 9000 series generation, so I'm not to sure about this - but I think those cards could be bottle necking you pretty bad .. those are pretty old cards, right?

The GTX series should give you a good boost. Maybe a GTX260? there cheap as hell atm. Or if you can spend a little more, GTX275. You could grab another later on also for SLI, when they get cheaper (with the 300 series coming out). As for your CPU, 3.6 is plenty for gaming.

If you could get those timings to CL4 and a little faster I'm sure that would help you out a bit.

TO THE FORUMS!!

about the bottleneck issue, when you oced the cpu that allowed the sli setup to be at its top game. no oc past 3.2ghz is going to give you a fsp increase with those card. since your at 3.6ghz now thats even better but not going to help. the next step would be to upgrade the video cards if you really wanted more fps. reason i say that is cause the 9600GT's are not that powerfull compare to a 9800GT/GTS/GTX/GTX+. the next part to move to is just what resolution your play at and if you use AA/AF? if you use AA/AF then no amount of ocing past (here agian) 3.2ghz is going to help. as the bottleneck has now shifted to the GPU. since running AA/AF that means the GPU has to go over the image agian and agian to remove jaggies and improve IQ. the cpu is mearly feeding the gpu's to do the work.

now if you do upgrade to a i7 system you could get single NV275/285 and get more FPS. then your current 9600GT sli setup, if i recall right a single GTX260 is about 2-3x times faster then a sli of the 9600GT's. keep in mind i havent been as active here within the past 2-3months so i could be a bit off. in how much more powerfull the GTX260 is to the sli'd 9600GT's.

without knowing the res your playing at ben. It's hard to say if you really need to run a sli setup on the i7 rig.

Thank you Metallica and Evilsizer! Both replies been great help!

Besides gaming I also do a fair bit of sound recording and editing, that's another reason why I was thinking of getting a quad. Also I've notice a lot of people in here are able to clock their 920 to 4Ghz which I think is amazing, and should help me gaining extra FPS in case of future graphic cards upgrading.

As per gaming, since my LCD runs a native resolution so I always stick with 1920x1080, and yes I do turn on AA/AF usually at 8x. And you right Evilsizer the AA/AF problem with my 9600GT is very noticeable when running later games like Crysis, though it's still fine with COD4.

Besides, I'm also thinking of getting either Vista or 7 to try and run games using DX10, thus the whole reason I'm thinking of upgrading my comp

Again, thanks.

the i7 d0's hit 4ghz pretty easy on air. even 4.2

So yeah, if you go i7, you would see a big increase with the editing/recording.

Your main issue is the GPU's atm. So either way, new card(s) would do you best right now. If money's not an issue, then do the whole shibang! i7/board/ram/gpu

You can get i7's pretty cheap now also.

yea ben COD4 engine is alot more optimized then the crysis engine. even crysis warhead the engine was much better but i dont know how much work they put into tweaking it compared to COD4.

i would skip vista, right now you can get win7 RC from MS and use it till june 01 2010. win7 is a tweaked and somewhat lightened vista from what i have read. i have the rc's downloaded from ms but no time to mess with it. now that it looks like i have some free time. i could use a new SSD drive to replace this older/smaller one. i will wind up putting win7 on the new SSD drive.

If you want to play games with better performance without spending a wad of cash, upgrade your GPUs for sure. At that resolution, and especially with those lower-end cards, your GPUs are your bottleneck right now. I think you could upgrade to a GTX 260 Core 216, GTX 275, Radeon 4870 1GB, or Radeon 4890.

An i7 will help improve SLI/Crossfire performance, but only with higher-end GPUs. Unless you're playing at 1024x768, you won't see any increase in performance using the same video cards. IMO, I would recommend against it, but if you want to use a GTX 295 or SLI some 285s, it would be much better to do so on an i7 platform. For the $$$/performance, I don't think it's a good value, but of course there are many people here who are willing to spend a lot for as much graphics horsepower as possible. I wouldn't recommend SLI'ing anything greater than some 260 Core 216s. And FYI, a GTX 295 is already two GPUs in SLI (essentially two lower-clocked 275s), so it will suffer from the same scaling issues.

Just ignore 3dmark06. It runs by default at a low resolution and is heavily CPU influenced.

First of all thanks for all the advices, so here is what I'm thinking of getting. (all prices are listed in $AU)

i7 920 - $275
Noctua U12P HSF - $89
Asus P6T Deluxe - $409
3 x 2GB Corsair Dominator C8 - $249
GTX275 - $290

Had a good look around for the prices couldn't believe GTX285 will set me back an extra $200 over the 275. So I've decided first to get the 275 and then SLI it if future need arise. I'll probably wait till mid Oct before getting this upgrade, reason is because Win7's coming out Oct 22, and there ain't many good games coming out till probably the end of this year (think COD6s coming out 17 Nov, christ sake Mass Effect 2 even 2010 Q1)

Meanwhile I'll start playing around and learn how to o/c other components in particular GPU. (in case things go wrong like punching a little too much juice / overheating etc I would then have an excuse to get my new system earlier )

Easiest way to tell if you're bottlenecked is to open task manager to the cpu usage graph and play your games at whatever res and settings you like for a few minutes. Then tab out and check cpu usage history. If the line is at the top of the chart all the way across the top or close to it then you could either use a better cpu or turn up your graphics more if frames are acceptable. Each game is different.