256Mb DDR2 £10.50

TheChillPill

Note this is the 'twice-as-fast-as-normal-ddr' ram, so if my understanding is correct a 256Mb chip of DDR2 will run as fast as a 512Mb chip of normal DDR (maybe not quite as fast, but faster in any case).

Aria have it on super-special for just over £10, which seems bloody good to me - if you have 4 slots available, thats a Gig of some of the fastest stuff around for £40!

Some tech blurb about it here if you want clarification, and of course as mentioned in that, remember to check that your board will support DDR2 (which I think means anything older than 1 year is very unlikely to).

redfox

the Crucial Memory Advisor is a useful tool for checking what sort of RAM your motherboard will take.

b44rch

TheChillPill wrote:

Aria have it on super-special for just over £10, which seems bloody good to me - if you have 4 slots available, thats a Gig of some of the fastest stuff around for £40!
QUOTE]

...which means you'll rule out any further upgrading - unless you replace the 256 sticks with 512 or a gig later on. Best to go for bigger sticks in my opinion, as a gig is pretty much the minimum you want these days.

TheChillPill

True, but it's significatly more expensive - plus remember this is DDR2, so 1GB of DDR2 is going to be substantially faster than normal DDR. I doubt most users would have a need for anything more than that unless you were doing very high end graphics or video.

To-poor

TheChillPill wrote:

Note this is the 'twice-as-fast-as-normal-ddr' ram, so if my understanding is correct a 256Mb chip of DDR2 will run as fast as a 512Mb chip of normal DDR (maybe not quite as fast, but faster in any case).

This isnt right mate. Yes the chip will run faster but if you dont actually have enough physical ram in your machine then no matter how fast the ram speed is your machine will actually run slower.

1x512 @ddr1 is much better than 1x256@ddr unless of course your going to run an os that only uses a tiny portion of memory (dos!).

Good deal if you have at least 3/4 slots though

TheChillPill

Yes, sorry - I didn't word that very well!

Basically, DDR2 has twice the bandwidth as regular ram, so it can handle more data and thus faster. Regular DDR with a clock frequency of 100Mhz will have a data output of 200Mhz. Whereas DDR2 with a clock frequency of 200Mhz will have a data output of 400Mhz and so on.

Not sure I agree with the 'no matter how fast the ram speed is your machine will actually run slower.' bit - unless you are referring to replacing a 512Mb DDR chip with a 256Mb DDR2 chip, in which case you are correct.

Best way to describe it would be to say that, like-for-like (ie a 256Mb DDR vs a 256Mb DDR2) the DDR2 should work virtually twice as fast.

scattycat_3

Must polnt out that with Aria Super Savers, you can only order 1 at a time, per day, and postage is £3.99

Hths

TheChillPill

Good point scattycat, thanks - had forgotten about that myself!

blinky

DDR2 is not backwards compatible with DDR(1).

Only some of the P4 motherboards support DDR2. In addition you'd want to put 2 sticks of the same memory (dual channel has a significant effect

Differences between DDR(1) and DDR2 are not that straightforward, in theory DDR2 is faster and provides greater bandwidth but most of the modules have poorer latency (access times), which is one reason why AMD hasn't switched to DDR2 yet (expected next year).

TheChillPill

Have spent a bit of time reading up on this today and found the following;

DDR2 has more pins than DDR, and hence you're board will either support one or the other (and obviously is not backwards compatible).

The reason AMD haven't switched to DDR2 is down to 2 things - firstly, their processor is less bandwidth heavy than the P4 range, and therefore of less benefit. Secondly, it would mean a switch to a different core.

Anyway, getting back to the original topic - if you already have a system running DDR2 ram, it's a good buy if you want more.

blinky

I knew about the bandwidth and latency but didn't want to get technical here