Buying new system... RAM question

[JohnE.]

Tomorrow I'm buying a used (1 month old) Asus A7N8X Deluxe Rev. 2 board. It comes with an Athlon XP 2200+ 266 FSB (not sure if it's Palamino or Thoroughbred yet, but doesn't matter at this point) and a Thermaltake Volcano 11 HSF. The seller won't sell separately (understandably... nor would I) so I'll have a CPU I can use right away, but the deal doesn't include any RAM. I'm saving $150.00 Canadian on this package over new parts, so it's a good deal for me, being on a tight budget and all.

I'll want to upgrade the CPU to a Barton core chip (probably a 2500+) as soon as I can afford it, and eventually a 3200+ (or higher when available and prices drop) so I'm wondering if I can purchase DDR400 RAM now and use it with the XP2200's 266 FSB or a 2500+'s 333 FSB without any problems.

I've heard Athlons work best when the RAM and the FSB speeds are synchronous. Can I "underclock" DDR400 RAM to 266/333Mhz via the BIOS so it runs synchronously with the CPU's FSB, or is this even necessary? Will the system autodetect a 266/333 FSB and run the RAM at 266/333 accordingly? Or should I be buying DDR266/333 for each CPU respectively? If prices eventually drop fast enough, perhaps I can skip the 333 FSB chip altogether and go for a 400 FSB chip.

Can't wait to get this puppy up and running! Btw... anyone interested in a used Athlon XP 2200+ in about, say, 2 or 3 months time? lol

JohnE.

[Telexen]

1. The 2200+ is a T-bred
2. The RAM clock and FSB will sync automatically...you have to manually change the DRAM settings for it to ever be different from the CPU, even if you overclock the CPU.
3. If you're going to buy a 333mhz FSB AthlonXP later, then your fastest solution will be PC2700 RAM because it's slightly faster than PC3200 because of latency timings...if you plan on ever going to a 400mhz FSB AthlonXP though you should consider the PC3200 now.

[JohnE.]

Thank-you, that clears things up a bit.

Since the parts are only 1 month old I'm assuming the 2200+ is a T-bred but weren't some of the early 2200+'s of the Palomino sort? A couple of forum posts I read at ncix.com seemed to suggest this was so, but they may have been in error.

I do plan on going to a 333 FSB chip asap (mainly for the Barton core) and a 400 FSB eventually when prices come down so it looks like PC3200 is probably my best option. I'll get the performance hit on the 333 FSB while I have it installed but won't take a $ loss on RAM upgrades. Since there's a performance hit when using PC3200 on a 333 FSB does this apply to using PC3200 on a 266 FSB as well?

Also, I'm not too familiar with Dual Channel DDR... how does that work? Do I need 2 (or more) RAM chips of the same size to get the advantages?

JohnE.

[wju425]

xp2100 was the highest palomino according to chipgeeks.

\o/ Billy

[cbuddha42]

yea no 2200 pal

you can get 3200 with timings just as fast as any 2700 its just gonna cost more

and it depends on your BIOS if it will auto sync - my mobo's (soyo kt333 ultra) default set my ddr333 ram to 333 and my 1800 to 266 - course it doesn't really matter as it takes all of about 30 secs to change

edit: 3200 will probably perform better at 400 than at 266sync

[JohnE.]

Getting up to speed on this stuff thanks to you guys, thanks for all the replies.

I picked up the mobo/cpu/hsf this afternoon and the 2200+ is indeed a T-Bred. The guy I bought it from thought that Palomino's were Duron only... unsure if that's true but it did ring a bell. Now I just need to know how to tell if the chip is a T-Bred A or B? Taking the HSF off and putting it back on looks kinda scary, lol.

Did a little reading up on DDR this evening... yes, you do need two sticks of the same size for Dual Channel (and preferrably the same brand/model). Sorta like matching drives for a RAID array I think. On the A7N8X the 2 parts have to be in DDR slot1 and slot3 with slot2 unused. I'm not sure but I assume this is true for other boards as well.

What kind of timings should I be looking at for the best performance once I get a 400FSB Barton? I read something about 2-2-2, 2-2-3, etc.

JohnE.

[cbuddha42]

2-3-2-6 T1 is probably the best you can find for 400

[RamonGTP]

Whatever you do, DO NOT waste your money on a Barton 3200+ CPU. Almost all the 2500+ Bartons will very easily overclock to 3200+ speeds. I overclocked mine to slightly past 3200+ speeds and saved myself $350 by doing so. If that 2200+ you've got is a Tbred B, you can overclock that to 2700+ with not much effort either, so you probably wouldn't even need to upgrade your CPU at all. What type of video card do you plan on running with the system?

[Telexen]

Originally posted by RamonGTP
Whatever you do, DO NOT waste your money on a Barton 3200+ CPU. Almost all the 2500+ Bartons will very easily overclock to 3200+ speeds. I overclocked mine to slightly past 3200+ speeds and saved myself $350 by doing so. If that 2200+ you've got is a Tbred B, you can overclock that to 2700+ with not much effort either, so you probably wouldn't even need to upgrade your CPU at all. What type of video card do you plan on running with the system?

They run on different FSBs...the mhz speed doesn't mean much and is NOT the same between them...you'd have to go a lot higher than the 3200+ speeds on a 2500+ to have a true comparison

[JohnE.]

Good point but, heh, by the time I can afford a 3200+ after I get new RAM, new CPU, new vid, serial ATA drives, etc., they'll be dirt cheap, lol. My first planned upgrade is to a 2500+ or 2600+. Good to know I can get 3200+ performance from a 2500+, thanks for the tip.

Telexen... between a 2200+ and a 3200+ yes, the FSB is different but afaik, all 2500+ are Barton 400 FSB.

Not sure about video card yet... the best I can afford when I'm ready to buy; an ATI 9600 Pro or an nVidia GeForce 4 Ti4200 perhaps.

Anyone have a link to info about how to tell a T-Bred "B" from an "A"?

JohnE.