View Full Version : Understanding CPU/GPU Scaling...

08-07-04, 03:08 AM
Hi All,
I read Anand's article (http://www.anandtech.com/cpuchipsets/showdoc.aspx?i=2149) on DOOM3 and CPU/GPU, and it made me wonder this:

CPU limited
When I have a slow CPU but a fast GPU.

GPU limited
When I have a fast CPU but a slow GPU.

My personal BIG question:
I have a P4 2.4b (slow CPU) and GeForce 6800 GT OC (fast GPU), so I need to get a fast CPU to keep up with my fast GPU, right?

If I had a P4 3.4EE and GeForce Ti4200, then I should get a GeForce 6800 Ultra OC to keep up with my fast CPU, am I correct?

p.s. on a side note, I am VERY tempted to buy an Athlon 64 FX-53 CPU (my very fist AMD CPU if I do so), but the price is very prohibitive. What would be the next comparable CPU at much, lower price?

Your insights, comments and posts are greatly appreciated.

Many thanks in advance.

08-07-04, 03:37 AM
What u say is right. My 6800 Ultra is held back by my Barton :(

I want a FX 53 too! :D

08-07-04, 03:50 AM
What type of DDR do you use with AMD MoBos? I have never used an AMD system.

08-07-04, 03:54 AM
The fastest u can use with non Opterons are DDR400, ie Athlon64 and FX53.

Opterons and Socket 940 FX cpus *I think* do not support DDR400 yet...and also they use registered memory.

08-07-04, 04:17 AM
Socket 940 and Opterons do support DDR400 bt only the registered type wich is more expensive. The next CPU close to the FX 53 is the AMD 64 3800+. People say it's nearly as fast. Hard to see the difference even in benchmarks.
IMO a 3500+ is more than enough though. 3800+ and FX 53 are overpriced but that#s typical for the best performinc piece of hardware on the market.

08-07-04, 04:29 AM
Ah S940s do support DDR400 then cool

08-07-04, 04:45 AM
It's also got to do with the settings. At 1024x768 you may be CPU limited, at 1600x1200 4xAA 8xAF you will more than likely be GPU limited. So if you have an averahe CPU (2500+/2.4GHz P4) and have a card capable of playing at these high settings, then your performance should be GPU limited, and your FPS will be very close to someone with a 3400+/3.4GHz P4.