Do I need more than 256M of RAM?

[ajmoss]

I use my computer mainly for video capture and editing. Transcoding a
file from MPEG-1 to DivX 5.02 isn't as fast as I would like.

Would I benefit from having more than 256M of DDRAM? The transcoding
is a serial operation, and so the computer only needs to store a few
frames at a time.

Let me put it another way. Would I be better off spending forty pounds
on a second 256M PC2100 DIMM, or should I spend that money upgrading
my Athlon XP 1800+ to an XP 2200+?

[Acaila]

I believe 256MB is already plenty of RAM for DivX5 to deal with. Things don't generally go faster with more RAM, only with faster RAM. Unless you're loading huge amounts of data into memory which DivX5 doesn't do, the encoding process is mainly arithmically intensive. So I believe your money would be much better spend on a faster CPU than on more RAM.

[theReal]

...but don't await wonders from an XP2200 when you're having an XP1800 now.
Video encoding is always too slow, believe me ;)

[JohnMK]

I personally would go with the additional RAM. Your computing experience will be much smoother as a result. Encoding speed won't be much faster (probably less than 0.5%, in fact), but I mean, heck -- using your computer while it's encoding or doing many things at once will be much more liquid.

[serbersan]

What system are you using? with NT, 2000, or XP you could use the system administrator to see how many memory your enconding is demanding and how many is demanading the wall system.

If your encoding demands less memory than you have... then the problem isn't your memory.

For example in my ATHLON 1.2Ghz 256Mb SDRAM. Virtualdub demands aprox 90Mb while I'm encoding with XviD a DVD. In total the system demands could be between 180 - 200Mb.

[cordraconis]

Wel, I am Encoding a divX right now @ AMD 1.9 Ghz (640*256, Sharp Bicubic resize, 31 Fps average) and my memory requirements are:

Virtualdub 1.4.10 : 81 MB of ram.

The total amount of memory in use is 333144 kB,
(System cache is 273796 kB, but that is because I use "Cachemanager 5.11 from Outer Technologies", and I tweaked my Windows XP Registry settings to a higher value. Needless to say, that my hard disks run very Smooth! :D , and network performance is also satisfying. (I'm running IIS to test-drive the website I'm building right now)

Moherboard is ASUS A7n266, with N-force chipset, and 2x 256Mb DDR installed. The performance difference in going from 256Mb to 512Mb was almost double FPS.

So to summarize: I'd go for the extra 256 Mb RAM, and then tweak your system to increase the Hard Disk cache, since HD's are generally the biggest bottlenecks in a system. Also don't forget to change the Latency's and delay's of your memory in your BIOS. (might save you a few minutes of encoding time). If you can overclock your CPU, please do so (be carefull dough :) ). Increasing the FSB, also increases your memory speed, and especially if you are running any filters [to sharpen the picture], this extra bandwith squeezes out more performance than installing a faster CPU. My AMD 1.9 overclocks nicely to a 2.1 Ghz. and it costs no money !!! ;)

greets,

Cordraconis

[Thermopyle]

Interesting, vdub only uses 81 megs, and yet going up to 512 doubled your frame rate (I assume you mean encoding framerate)?!?

And increasing hard disk cache size over XP's default only increases performance on some tasks, but slows system performance on other tasks.

However, regardless of those doubts, I'd recommend the memory upgrade as well, because there won't be much of a performance difference between an 1800+ and a 2100+, but the extra RAM will increase general system "smoothness".

[dTb]

Originally posted by cordraconis


Moherboard is ASUS A7n266, with N-force chipset, and 2x 256Mb DDR installed. The performance difference in going from 256Mb to 512Mb was almost double FPS.



It sounds like this could be due to the n-force chipset more so than the extra ram. IIRC using two sticks as opposed to one theoretically doubles the bandwith.