Which is better: RAM Timings or RAM amount?

[se7en16]

My current setup:
ASUS M2N4-SLI mobo
AMD Athlon 64 3800+ @ 2.4 Ghz
1 GB Corsair XMS2 DDR2 800 (PC2 6400) RAM

The timings on my current RAM are 5-5-5-12. I'm thinking of getting more RAM, but here is my question.

Which is better?

3 GB of Corsair XMS2 DDR2 800 (PC2 6400) RAM @ 5-5-5-12
or
2 GB of Corsair XMS2 DDR2 800 (PC2 6400) RAM @ 4-4-4-12 (with EPP)

I'm currently going back and forth between XP and Vista (not going full time with Vista until most of the kinks are worked out...).

 

[nullpointerus]

Hmm...given your situation, it could go either way.

I would pick the 3 GB setup because of multitasking and possibly using Vista in the future. Waiting for the HDD to stop churning after you quit a game is frustrating, and extra RAM will greatly increase your disk cache in Vista. You can't possibly notice slightly faster timings to the same degree.

 

[Yellowbeard]

In almost any given situation the 3gb will outperform the 2 except for raw memory bandwidth in synthetic benchmarks. Are you planning on adding a pair of memory so that you stay in dual channel?

 

[aka1nas]

The difference between low latency and high latency RAM is usually only noticeable in memory-oriented benchmarks, not in real-world apps. Having the extra RAM will have an actual performance impact if your workload uses that much.

 

[JustaGeek]

I would pick 3GB of "slower" RAM, in Dual Channel (very important!), but to use it in a 32 bit OS you must activate /3GB switch in the boot.ini file, and have applications that can take advantage of the 3GB RAM.

Almost all programs designed for 32 bit OS' have 2GB upper limit for RAM, and will not go beyond that. I got mine because Quake 4 was little "jittery" in Ultra Quality settings, and the RAM use was 99% (Logitech G15 keyboard software). It shows up to 66% RAM use now (consistent with the 2GB upper limit for applications), but the jittering seems to be gone! Guess the system makes good use of the increased RAM, and uses it instead of the Swap file on the HardDrive.

Or... you can get 2x512MB, for a total of 2GB, and avoid the above problems altogether...

 

[Conky]

More RAM would be better.

I have that same Corsair 5-5-5-12 and it runs 4-4-4-12 with no problem (just a change in the BIOS although some might have to bump the voltage a bit).

And unless you have a motherboard an Nvidia 680i chipset the EPP function is useless.

 

[JustaGeek]

I have the NVidia 650i chipset, and I agree that EPP is not only useless, but sometimes it may contribute to the boot failure.

If you reset the CMOS, the BIOS will read the EPP instead of the relaxed timings for the memory, use default voltage of 1.8 or 1.9, and you might not be able to boot, even to change the timings/voltage!

In Nvidia 650i and 680i chipsets on Intel MB's all the settings must be done manually in BIOS.