Some advice on PC memory (DDR/SDRAM)

I’m working on building myself a top o’ the line PC. Right now I’m leaning towards a P4 2GHz and some kind of badass GeForce 128MB graphics card.

Basically, I’ll be using this thing for 3D gaming, as anything else I could want to do (internet browsing, burning cds etc) I can easily already do on the laptop I’m using now (P3 1Ghz, shitty onboard video).

Now here comes the question: memory.

I’m aware that DDR memory is far superior (benchmarks and whatnot) to PC133 SDRAM. But, its also much more expensive. I did say I’m trying for top o’ the line, but I’m also not made of money. I can buy 2 512MB PC133 chips for $25 each. (yeah its generic, but I don’t care). OR I can buy 1 512MB DDR for possibly $100 or more.

I’m thinking, if Ive got a kickass video card with lots of video memory, AND I’ve got over 1GB if system memory, am I really gonna see any difference.

Any experience with this? Whats better, faster memory or MORE memory? Any input is appreciated.

BTW my motherboard (will) have slots for both.

First of all, I would suggest you go with an AMD processor-based system. You can get a much faster AMD-based system for the same price as a P4 2Ghz system. I would also suggest you go with an ATI Radeon 9700 Pro over a Geforce4. The Radeon 9700 Pro is currently the fastest graphics card on the market.

Now, down to just the memory, you’ve GOT TO go for DDR. A P4 takes an INCREDIBLE performance hit when it isn’t fed lots of memory bandwidth, and an Athlon XP would experience a similar impact. You’ll want to go with a motherboard that supports and allows you to fully utilize AT LEAST PC2700 (DDR333), and preferably PC3200 (DDR400). DDR333 has 2.5 times the bandwidth of PC133 SDRAM, and DDR400 has about 3 times. This memory bandwidth really is needed by modern processors, especially the P4.

One final caveat, don’t go with a cheap motherboard. The motherboard is the most important part of the system, cheaping out and going for a generic will only give you an unstable system. My personal favorite is Abit, but as long as you stay away from PC Chips and the other generic companies, you can’t go TOO wrong.

I don’t think if you have over 1 gig of ram that you will see any difference, aside from having a lot of stuff open. Then again, I might be wrong.

I second FDISK’s remark about the whole cheap motherboard thing. Go with Abit or Asus. I have a freakin Jetway, and it just blows. I was on a tight budget, and thought it would be alright. I shoulda held on a few days and gotten something worthwhile.

I have a 867AS Jetway mobo, with an Athlon XP, and 512MB ram, and despite the downfall of the motherboard, this setup enables me to do alot. I can burn cd’s, surf the web, and program stuff in without any lag or problems. Not to mention listening to music and downloading stuff from the net. Quite proficient.

Other threads for you to read:


Building my own PC

I’m building myself a PC!

Thanks guy, I really appreciate the responses. I’m just not sure. I’m still not really convinced that 1Gig of Pc133 RAm is gonna slow my system down.

I believe what FDISK says and I KNOW that DDR is superior, but for my purpose of Gaming, am I better with 1Gig PC133 or 512DDR? This is my basic question. Any specific experience here?

For gaming purposes you are better off with 512MB of DDR. AMD CPUs are somewhat less memory-bandwidth hungry than the P4s, but it still makes a noticeable difference. For most users, 512 MB is about the maximum amount of memory you will need as well. If you were doing graphic design or 3D animation work, 1GB might be useful. But for home use (even gaming) 512 of faster memory will likely be much better. After 512 MB, the benefits don’t increase all that much.

FDISK is on target with everything he said too. AMD chips are a much better deal in terms of ‘performance per dollar’ currently, and for most home users that is the important criteria. Also, you said that you didn’t care about your memory being generic. I urge you to reconsider! Cheap memory can be a great source of frustration as it can lead to all kinds of instability in a system. You don’t have to get the highest-end stuff around, but I recommend getting a decent brand. Of course it will cost more, but keep in mind that gaming is actually a pretty demanding computing task.

It sounds like you’ve either already got a motherboard or you have one picked out. In case it’s not too late to change directions, I’ll give my specific system recommendations based on several systems I just built and comparing the performance between them.
Motherboard: Gigabyte GA-7VAX, $89. Recommend motherboard with VIA KT333 or KT400 chipset. I’ve had good luck with Asus, MSI and Gigabyte. ABIT is ok too. Gigabyte seems to be the best deal right now.
RAM: 512 MB Mushkin PC2700 DDR, $154. Recommend any good brand of DDR memory.
CPU: AMD Athlon XP 1900+, $85. Any current AMD CPU, depending on how much you want to spend.
Video Card: This is harder. For high-end, ATI Radeon 9700 Pro at $330. For lower cost, Geforce 4 Ti 4200 at $130. I personally would probably go with the lower priced card right now and consider upgrading later on. But if you want the absolute best available right now, the Radeon 9700 is it.

I just built my new gaming machine two weeks ago. I’d highly recommend an MCI motherboard (and video card). And I’ll fourth the need for DDR RAM. You’re better off w/ 512 DDR than with 1G SDRAM. You go with SDRAM and you are stuck with the performance hit forevermore.

Additionally, most good motherboards are DDR only. Dual purpose generally are not performance boards. It will probably only be rated for PC2100 DDR, which limits total upgradability.

I’d recommend an Athlon system (go about 2200+, will be cheaper and as fast/faster than a P4 2000) and an GeForce Ti4200 with the DDR RAM. Best bang for the buck. Sure the ATI Radeon 9700 Pro is the fastest gun in the west, but you can get the Ti4200 at less than 1/2 the price, and the 9700 does not provide twice the performance. With the savings, go for PC2700 DDR and a motherboard capable of handling it.

While FDISK is right about PC3200 being better, without the right motherboard it’s wasting money, and it’s the most expensive option, both memory and mobo-wise.

Good luck and good gaming.

While we’re on the subject…

I’m looking into a new video card, and I was planning to go with a PNY GeForce4. However, I’m torn between the 64MB and the 128MB version. (Both are DDR.) As a semi-serious gamer, how much difference is the extra 64MB going to make? The price difference appears to be about $50. I have an Athlon XP 1800 and 512 MB of DDR in my system.

Dr. J

I don’t believe any of today’s games take advantage of the extra memory. It depends on the how crazed you will be about framerate, fill distance, etc. 12 months from now. Games will grow into 128mb, but still should look pretty good on 64. 64mb should serve you well for the next 2 years. Then you won’t feel so guilty when you upgrade to the GeForce 10 or Radeon 155000 while I’m still on my GeForce 4.

Tom’s Hardware Guide has an article on 333 memory vs. 266 . The relevant page within the article is the one showing gaming stats (look for the Direct3D Benchmarks). Though the practical difference between 333 and 266 is fairly minor, the advantage of 333 over 133 is apparant and significant.

Similar, more recent articles discuss motherboards with the newer DDR400 chipsets. The upshot is that the memory difference is not as important as the new boards offering of additional features, including AGP 8x, though taking advantage of some of these features requires fairly expensive hardware.

In all, I’d spend a little extra dough now than regret being stuck with a bottleneck later.

I guess I’ll defer to the wisdom of the massess on this one and go for DDR. Is ECS a cheapo board? I’ve been using generic memeory and mobos my whole computing life and Ive never had any problems.

As I understand it, the AthalonXP 2200+ is 1.8Ghz. with 266 FSB compared to the P4 at 2GHz with 400FSB. Right? I may be confused here. Anyway, tells me that the mobo+cpu combo for the Athalon is more expensive.

What gives?

Jayrot: I really doubt you can make use of more than 512MB RAM. 512MB is a LOT of memory. If you aren’t utilizing the extra RAM, it causes no performance benefits. On the other hand, Going from DDR to PC133 causes a HUGE performance penalty. Modern chips really do REQUIRE the extra bandwidth. The only case in which I could justify using PC133 instead of DDR is in a computer that would never be used for gaming, only for web browsing. For an AMD right now I’d go for PC2700, unless you’re sure you won’t be overclocking or upgrading to faster Athlon XPs. For P4s, I’d go with the fastest RAM the motherboard will support and get a motherboard that at LEAST does PC2700, preferably PC3200.

On the subject of chipsets, for AMD the FSB has a bandwidth of 2.1GB/sec (Increased to 2.7GB/sec on the new XP 2800+). Trying to push more memory bandwidth than that is an excercise in futility that can only DECREASE performance, since the bus just isn’t big enough to accomodate it. On a P4 system, however, the FSB has 4.2GB/sec of memory bandwidth. On a chipset that supports the faster RAM, you will see performance rise as you feed the CPU more and more memory bandwidth. The reason RDRAM doesn’t perform too well is that while it has a lot of bandwidth, its latency is terrible, reducing overall performance.

Hope this helps!

Jayrot: Dang, posted just after you said that. Anyway, ECS isn’t necessarily bad (#1 mobo manufacturer worldwide, they fab Abit and most other boards) but they aren’t really quality either. I’d go for a nice Abit AT7-MAX2 or Abit KD7 motherboard or, if you need to save money, an Abit KX7-333. The KX7-333 can be had for well under $100. You can get a KX7-333R with RAID for slightly more, IMHO worth the price, but its your call. If you’re going for absolute lowest price, an ECS K7S5A motherboard with PC2100 DDR for an Athlon XP would work well. The K7S5A is rather stable when paired with good RAM and a good power supply, and is under $50. Unfortunately, it does not support the newest AMD CPUs, and will be somewhat slower than a good Via KT333 or KT400 based motherboard.

The Athlon XP 2200+ is meant to compete quite well with the Pentium 4-A 2.2GHz. In general, a specific model Athlon XP is about as fast as a similar Mhz P4. An Athlon XP 2000+ is really the best value at the moment, as it can be had for cheaper than a P4 1.6Ghz, and will beat on a P4-A 2Ghz quite well. The XP 2200+ is priced about the same as a P4 2.0Ghz, but the extra $100 would probably be better spent on something that will get you more than another 133Mhz of CPU clock, like a better videocard (Radeon 9700 Pro baby!).

The reality of the FSB is that AMD uses a 133Mhz DDR FSB on its midrange/low-end XPs, for a claimed FSB of 266Mhz. Intel uses a 100Mhz QDR (Quad Data Rate) FSB on the P4 and P4-A, for a claimed FSB of 400Mhz. The 400Mhz QDR FSB will have more overall bandwidth, but the 266Mhz DDR FSB will have lower latency. They can compete with eachother quite well, performance wise.

FDISK : Thanks for all your (very knowledgeable) input. I know this is like the "N"th thread of its kind, but I love the SDMB because people still seem to care (like you). Much appreciated.

I haven’t bought a single thing yet, so I’m really trying to evaluate all these options. Unfortunately, I’m not working now so money is rather tight. I wouldn’t even be considering a new system if it weren’t for the fact that I had my hopes set on Neverwinter Nights and I went out and bought the damn thing for $50+ only to find the manual saying it’s incompatable with my graphics type (SiS).

So now that I think about it, I’m really buying a new computer just to play a game (pretty silly huh?). Anyway, I’m not so obsessed with framerate and whatnot as I’ve been playing 3d games on what Ive got now.

One last question:
ATI Radeon 9000 128MB
Apollo GeForce3 Ti200 128MB

I know that neither is the best these days, but for 100 it's what I'm considering at the moment. I guess I could spend the extra 40-50 to get something more badass, but really, as I said, I’m just interested in playing with no lag. I don’t really care about super framerate at 1600X resolution or whatever.


Grr. I swear I posted this yesterday evening. Anyway…I’d go with a Radeon 9000 over any member of the GF3 series. I’m not sure on release dates, but there is a new card called the Radeon 9500 on the way out. It’s meant to be faster than the 9000, but cheaper than the 9700. However, if you’re buying now its clearly not an option. The Radeon 9000 should be more than fast enough for your needs, and is loaded with features.

One last thing I wanted to mention was to make sure you have a good case and power supply. The case must have at least two ventillation fans (generally an intake in front, and an exhaust fan next to the CPU in the rear), and the power supply should be at least 300W, preferably 350-400W.