I’ve googled myself to death on this, and haven’t found a clear recommendation, so I humbly submit for your perusal:
I currently have an AthlonXP 1800+ CPU on an MSI motherboard (KT3 Ultra 20-C/VIA KT333 chipset), 256 MB of PC2100 RAM. Currently, use it to access the web, and play games - mainly Unreal Tourney 2k4, but some other less graphic intense games.
Given that I currently get about 10 frames/sec in UT with moderate quality, I am looking for a performance boost, and plan on adding up to 512MB RAM (no more than that - $) and upgrading the CPU; I’ll also be upgrading from a GeForce MX440 to a Radeon 9700 Pro - yummy).
Since the mobo only supports CPUs with a 266 Front Side Bus, I have to add an AthlonXP 2400+ (Thoroughbred core, not the new Barton 333/400 FSB CPU) - got that figured out.
The mobo supports up to PC2700 RAM. If I keep my existing PC2100 RAM, I won’t bother to get PC2700 for hte new stuff, because the memory speed is dictated by the slowest RAM stick, and I won’t be buying a new PC for a while - by then PC2700 will be ancient. So I have two choices: increase my memory bandwidth from the current 2.1 GB/sec to 2.7, with only 512MB capacity; or staying at 2.1GB/sec, but increase total capacity to 768MB.
Finally to the question at hand: which is more of a performance boost for gaming - 512MB total at the faster 2.7GB/sec throughput, or 768 at the current throughput?
Compounding this issue, I’ve heard conflicting reports on other forums on a couple points - I’ve seen some say that once you’re above 512, performance boost form addt’l RAM is minimal unless you’re rendering 3D, or processing/editing video realtime (so why have 768 when 512 is all you’ll need); but some others say bollocks to that, 1 GB or above is where performance tops out (I tend to belive the latter, but IANA hardware expert). I’ve also seen some people say that the CPU Front Side Bus limits the memory throughput in those mobos (like mine) which support different maximum CPU (266) and RAM (333) FSB speeds; I haven’t seen anything refuting this last point, but not sure - although it’s curious why anyone would bother to support faster RAM when the CPU will just throttle it back. If this is indeed that case, then PC2700 would result in a negligible performance boost. I have also heard (but not confirmed) that filling all memory slots on your mobo (mine has 2) will drag throughput down.
Any ideas?