SLI is completely irrelevant, since it is not supported.
A LGA 775 board is pretty old and uses DDR2 memory. You did not tell what CPU is installed, but likely it is something like a Q6600 or Q6700. Also you forgot to mention what kind of source material you will be editing.
If AVCHD material and the assumption about the CPU is correct, then whatever memory you install, the CPU is around the absolute bare minimum and will not give you a nice editing experience.
Upgrading from 2 x 2 GB to 4 x 4 GB means that your current memory will be useless. If you decide to upgrade your system in the future, this memory will be useless as well, since newer systems require DDR3 memory.
I think you also have to consider a new system. Have a look here: Adobe Forums: What PC to build?
and look at the economical model suggestions.
Harm I value your input, Oops my bad this Asus P5q3 mother board is a Dual-channel DDR3 and CPU is a Quadcore Q8300 at 2.50 , display card is gts250 , it also has a 2 x PCI Express 2.0 which I was informed a few minute ago that I am able to use the Geforce gtx280...... ,if this is so about this MB would this be alright to use . Another ? if did not go the 4gig ram modules and only use the full 2x2 +8gigs modules and replace the Display card with the GTX285 would the PC be useable to run CS5, as I am whieghing up if i should upgrade the current PC or get a new MB ,12gigs ram, CPU and GTX285.
Currently I edit using GV Edius 4.61 as my main editing , PPro2 and CS4 PPro to do stuff my edius is not able to do very eazy eg Keying , titeling and SD dvd out I edit SD, HDV and will be getting a Canon 550d/Ti2
Sorry for the lack of info but been in africa we are a bit on the slow side , even slower than in deep south of USA
Thanks for the additional info. That makes it a lot easier to give some feedback.
The Q8300 comes up once in the http://ppbm4.com benchmark with a score of 113.5 seconds. Look at the results to where your system may end up in the ranking, or even better, do the test yourself, submit the results to Bill and your results will be included. You can also send them to me by PM.
DDR3 memory is available in 4 GB sticks maximum. There are no 8 GB sticks in the 1600 speed.
You will need 4, so in local prices prepare to spend € 900 for four sticks or more. But the main advantage is that this memory can be ported to a new system, so that investment looks interesting.
I would wait with investing in the GTX-285, which is end-of-the-line and see if the performance gain of CS5 will suffice for the time being and then wait for benchmarks to appear that show the gains from a certified card and possibly the Q3 GTX-480 support. I will wait for the results of the 480 in some benchmarks when it is supported and will bypass the 285.
I expect your system to be around two to three times slower than the top performing machines with CS4. You will also notice when looking at the benchmark results that disk setup is a very important factor.
Thank you Harm , after looking at the tests done and similar spec to my setup it is abit disconcerting to see that I will have to spend a lot of money to upgrade agian. In the current form to get the full 16gigs of ram working and getting a new card works out about the same as getting a new MotherBoard , 12gig's ram , core7 930 and display card. I now have to choose between a high end Laptop or upgrading hmmm this is giong to be a hard one