4GB @ 333 or 2GB @ 400?

By Starsky303 ยท 12 replies
May 10, 2007
  1. Hi all,

    I've been using 2gb RAM on my computer for some time now and have recently updated my bios and added another 2gb so my bios now reads the full amount but says 333 DDR Dual "" instead of 400 DDR Dual "".

    I've been reading other posts and knew there was an issue with windows not reading the full amount of RAM (mine's set to 3gb) but I'd like to know...
    which is better? Having 4gb running at 333mhz or 2gb running at 400mhz?

    Sorry if the answer I'm looking for IS that obvious, but I'm sure I've read somewhere there's no difference if not worse for having 4gb running at 333mhz.

    Your thoughts and help would be much appreciated!

    Asus A8N SLI Deluxe
    Athlon 64 FX-55
    XFX GeForce 8800 GTX XT
    2x TWINX2048-3200C2PT (4GB) RAM
    Maxtor 6B300S0 300GB HD
    SB Audigy 2 ZS
    Windows XP Home Edition
  2. SNGX1275

    SNGX1275 TS Forces Special Posts: 10,742   +422

    2 Gigs @ 400. XP Home (and XP Pro) aren't going to give you 4 gigs to work with anyway. If you want to use 4 gigs get a 64 bit OS.
  3. Tedster

    Tedster Techspot old timer..... Posts: 6,002   +15

    of course all your ram is the same brand and type and you did read the installing ram guide in the guides forum....
  4. captaincranky

    captaincranky TechSpot Addict Posts: 13,026   +2,557

    Well, Here Goes......

    First, is that 4GB recognized in Windows, or just BIOS.

    The performance jump from 512MB to 1GB of RAM is truly impressive.

    The step up to 2GB is noticeable, but not like the foregoing.

    The move to 4GB is not anywhere near the other 2.

    Windows limits any one app to 2GB. (Yes I know about the "3 GB switch").

    So, in practical terms, unless you're doing heavy multi-tasking, 2 GB is plenty. (At least for XP).
    I do admit that 4 Gigs on board is a great talking point.

    As to speed, more memory is usually as good as faster, but you've hit the point of diminishing returns (with respect to more), so who knows.

    How did you manage the speed drop BTW?

    Why not experiment? Have Nero recode do an advanced analysis on a dual layer DVD, to be compressed to a single layer DVD. You wouldn't have to actually burn it. Nero Recode's advanced analysis function uses as much or more RAM than any program I've seen.
  5. Starsky303

    Starsky303 TS Rookie Topic Starter Posts: 47

    Thanks for you help guys, I needed it!

    Tedster, RAM is all the same model/make.
    Capt. 4GB is recognised in BIOS only as Windows recognises 3GB (I guess the other's allocated to my grphx card or something (?!).
    Still not sure whether or not I should keep them in now, use my pc for photoshop and gaming mainly.
    What did you mean by 'speed drop'?

    Also, why is my computer setting the memory speed to 333mhz Dual Channel on 4GB but 400mhz Dual Channel on 2GB?
  6. captaincranky

    captaincranky TechSpot Addict Posts: 13,026   +2,557

    Computers, just like contrary children they are......

    Windows 32 bit can only access 4GB of memory total. The missing 1GB is used by the BIOS as hardware addresses, hence it's invisible to the OS.

    Some boards reduce the speed of the memory when it's at full capacity.

    Photoshop is a memory hog and can be configured to usage of a specific percentage memory. Ironically, the more memory in the machine the higher the percentage that should be set. With a 32 bit board and OS you could have quit at 3GB and gotten the same results.

    I don't know that it's necessary to remove the extra RAM. If you sack 1GB of what you have, it will no longer be dual channel.
    If you install 2 512s they'll, 1. cost you more money, 2. may or may not run at 400MHz.

    We stiil need to figure out if the reduction in speed is perceptible in real world usage.
    With 3GB of memory available and no modifications to the OS, the programs get a full 2GB, with nothing subtracted to run the computer.

    As I think I might understand it DDR (dual data rate) RAM at 333MHz has a throughput of 666MHz, double that for dual channel operation. Point being, it's moving right along. I hope that's right.
  7. Starsky303

    Starsky303 TS Rookie Topic Starter Posts: 47

    Why do some boards reduce the speed of the memory?

    Anyway, I'll trust what you said about programs getting the full 2GB with nothing subtracted to run the computer. I reckon you're right.

    Before I updated the BIOS and tried to run with 4GB, it was as if Windows was constantly looking for something or didn't what to do with itself (if that makes sense). BIOS read something like 3.25GB while the Windows memory was set to something random like 2.63GB?! Constant caching.

    Now with the new BIOS there's none of that. BIOS reads 4GB, windows reads an understandable 3GB and there's no caching. I'm gonna keep 'em in!

    Thanks for that Cappy. You've been extremely helpful mate!
  8. Soulhunter

    Soulhunter TS Rookie

    ooh, I bet it has to do with your use of dual channel RAM. (the speed drop). So, if you removed one RAM module, your BIOS would show 3G RAM, windows would also show 3G RAM at 333 (actually a little less, since the BIOS would reserve some of your RAM for hardware addressing). Removing two RAM modules would drop your RAM readout in your BIOS to 2G and a little less than 2G in windows, but at 400Mhz speed.

    1) Replace two of your 1G modules with 2 512M modules so you can get 3Gigs of dual-channel 400Mhz support
    2) Leave the 4G in, test if a different OS will see and use the full 4G at 400mhz. Vista may support it, or one of the linux flavors.
  9. SNGX1275

    SNGX1275 TS Forces Special Posts: 10,742   +422

    It is unlikely it is a board problem with 4 gigs, the only modern board I know of that fights with that (although there may be others) is the Asus P5n32-SLI. But 32bit OSes can't handle 4 gigs of RAM, so there is no need to worry about that. If the board can take it, the 4 gigs will fully show up in a 64 bit OS though.
  10. Starsky303

    Starsky303 TS Rookie Topic Starter Posts: 47

    Yeah, that's what I was thinking. I'd like to upgrade to Vista to get my full fat 4GB but Vista seems flaming problematic at the moment. XP really only became popular after Service Pack 2. Will upgrade to Vista when DX10 comes out. Until then it's grin and bear the 3GB Dual Channel @ 333Mhz. I shouldn't complain really as it's fast enough already!

    Many thanks all. Love these forums!
  11. captaincranky

    captaincranky TechSpot Addict Posts: 13,026   +2,557


    No, Vista 32 bit at the moment is a headache, however I fear that 64 bit Vista would be a much bigger pain further south.

    There are other factors that affect execution speed besides RAM frequency.

    Unless you can prove to yourself that less memory running faster works better than more running slightly slower, leave I in, (It's free at this point).

    A retraction/ correction of an earlier statement by; Nero Recode uses almost of the processor and not very much RAM when doing advanced analysis and burning from AA. (great test of CPU heating). However, when burning direct to disc from a folder it uses as much RAM as the system will permit.

    I still think Photoshop should tell you a great deal of what you need to know. Start with the biggest photo file you can muster, pull up task manager, and start applying filters. See what happens, bring your stopwatch. Don't forget to configure PS to a percentage of RAM usage equal to 2GBs.

    There's always 64 bit XP Pro. I have no opinion there, just there's always 64 bit XP Pro.
  12. SageOfTheWabash

    SageOfTheWabash TS Rookie Posts: 24

    Are you saying that Windows XP 32bit will never recognize 4 gigs of ram? If so, I just waisted some change. Ouch!!!
  13. Starsky303

    Starsky303 TS Rookie Topic Starter Posts: 47

    No worries mate. That's the mistake I made too. Bought 2GB then thought... sod it, my motherboard supports up to 4 so dammit I'm gonna give it 4! It's not a bad thing really, just look at yourself being extremely 'Vista ready'! (bloody memory hog) :)
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