There has been alot of talkabout the Playstation 3’s Random Access Memory (RAM) vs Xbox 360’s RAM, saying that the 360 has more RAM to work with etc. Here’s an article to explain the situation of its RAM.

Just so you know that the PS3 has 512MB of RAM (256 for video and 256 for system). The Cell chip has 256MB of completely sharable RAM, the GPU has 256MB of dedicated RAM. Now the key here is what type of RAM it is.

The Playstation 3 has 256mb of GDDR3 at 700mhz and 256Mb of XDR at 3.2ghz. So what exactly is XDR ram? Here are some of the highlights:

• XDR makes PS3 super effiecient
• XDR aids in faster cache mapping, both direct and indirect
• XDR ram works by a pointer to pointer technology and needs very small buswidth for execution
• XDR is not just faster than GDDR3 but it is much more efficient
• XDR RAM works by breaking down data into several packets which prevents data loss and exceptions

“The Rambus XDR™ memory architecture is a total memory system solution that achieves an order of magnitude higher performance than today’s standard memories while utilizing the fewest ICs. Perfect for compute and consumer electronics applications”

The PS3 has two times as much cache at 2x the speed, making it way faster for direct/indirect mapping. Not only that but it has 512k of L1 cache + 1.7m of L2 cache for the 7 spes. The PS3’s GPU, RSX was made to work with the Cell processor, it is not some GPU they took and slotted in. It is made to be compatible with the Cell.

More RAM does not mean a faster system it means more data can be stored in a fast access area. Games don’t always need 512mb of RAM.

The RSX can freely use as much of the 512MB total RAM that the PS3 has because the Cell doesn’t need much RAM because its fast enough. And the fact that the PS3 has XDR means that it has faster access to data files.

A lot of people are saying that the RSX only has 256mb of RAM, whereas the 360’s GPU has 512MB of RAM. To make it sound a bit simpler, here’s the real deal. The PS3 has it’s RAM in two separate parts, 256MB for the RSX and 256MB that can be used be either the Cell or RSX.



文章过长就不翻译了，大家肯定也看得懂，大致意思就是“PS3的RAM分为两部分，一半用于RSX的GDDR3，一半用于CELL的XDR，而360是512MB的GDDR3的RAM，虽然看上去PS3的显存RAM比360少，但是CELL的那部分是可以共享，RSX完全可以用到512MB的全部RAM，所以和360的Xenos没什么区别”

嘿嘿...沒什麼區別?*/-19

你认为有什么区别的话，不妨找一个画质比Uncharted更好，loading时间更短而且不用硬盘安装的游戏出来么，谢谢！

GOW行不?當然在天師無敵的KZ2面前都成渣了*/-19
比獨佔遊戲其實沒什麼意思,就是要跨平台才能顯現兩平台上的性能差異*/-49

嗯，按照同学你的逻辑，如果有PC版本做的比console要差，那么性能优越者是console？*/-34


要证明capability，自然只能拿各自最好的出来比较啊，不相上下是一种结论，互分高下也是一个结论

只有一款遊戲那是特例,但當10款遊戲有9款如此時那就是常態了
FIFA PC版不如360版,但DMC4.NFS.LP.C&C3.GOW.BIOSHOCK這些遊戲PC都顯然較優
當然如果你想把特例當常例我不會阻止的*/-19

特例？嘿嘿


要不要我把上个世代从PS2移植到PC上的诸多破烂作品列举出来？PC那个时候莫非不如PS2了？*/-19

这个所谓优劣，无非是以什么平台为leading platform 罢了。*/-48
本世代PC开发和360平台开发因为M$的缘故可谓一脉相承，作为开发体系有异的PS3如果不是leading platform，那么会吃亏我看不出有什么奇怪的。

跟PC一脈相承?*/-93
真的能做到這樣那也是因為MS的開發工具太好了,360在硬體本質上跟PC有非常大的不同
PC上的GPU有辦法直讀CPU L2?Xenon是PPC架構還是X86架構?
leading platform例子是有的,BURNOUT PARADIASE的AF差異看見沒有?*/-34
性能特性上的差異是存在的,不會因為以哪個平台做Leading Platform而消失

[本帖最后由 allensakura 于 2008-7-12 16:13 编辑]

和我没关系*/-25

说的就是你。*/-19

这个贴不是我转的，我才回来*/-52

越描越黑。 明明是你转的，这个帖子的作者是不是你？ 开始磨刀。。。

不知道，估计账号被盗了，我是被冤枉的*/-16

就是這種P文還有人相信才糟糕*/-34
XDR距離RSX太遠了，頻寬太小和延遲太大
部份資料放XDR加速可以,當一般的繪圖記憶體使用7900跑起來都會變7600
還有RSX沒有EDRAM，FRAME BUFFER所佔用的記憶體多的多了

按照你这种说法，R&C:TOD, Uncharted, GT5P, MGS4 的画面都是天顶星人科技在作怪*/-19
话说黑PS3的人，一直无法解释他们的“黑”理论跟那些画面优秀的作品到底是如何并存的咧

他们说那是美工画出来的*/-19 */-19 */-19

说是美工不能算错。 MGS4在1024x768这种分辨率我在Raiden跟Vamp以及Raiden对付Metal Gear的场景明显有慢下来的情况。Liquid Snake在让克隆士兵发疯的时候也能觉得慢下来。以PS3的机能在1024就稍微有点卡，我还能说什么呢。

MGS4里头比那两个场景复杂的多的是。唯一一个让我感觉慢了下来的场景，是Rex VS Ray

你这叫反应迟钝。 多玩玩FPS吧。*/-48 */-34

多GPU的延迟也不是谁都能察觉的，就像DLP的rainbow效果，还有LCD的input lag等等。

沒人可以否認美工的重要性
GOW的畫面表現美工也佔非常重要的地位
那本GOW美術設定集可是美工必讀之書阿
至於那些PS3獨占遊戲
我的看法是如果能上360，10個有9個能有更好的畫面表現*/-34
MGS4跨平台小道消息不斷，如果真的跨了到時畫面比較希望你別跑*/-48

啧啧，时至今日，还来跨平台小道消息不断。*/-19
果然一个MGS4逼疯了许多有的没的人士

顺便跟你说说，目前PS3上面，画面成就最高的是Uncharted，你不妨也去YY一下顽皮狗跨平台吧。

反应迟钝？恰恰相反，俺不玩FPS的原因我不早说过了么？我会motion sick。

帧率不足的话，俺很容易感觉出来的。而且是代价比较惨重的那种“感觉出来”*/-41

我认识的不少人也是玩不得FPS 玩起来容易头晕甚至呕吐 这个病症M兄能给个百科链接看一下吗？

寒，英文，暂且看一看吧

Simulation sickness

Simulation sickness, or simulator sickness, is a condition where a person exhibits symptoms similar to motion sickness caused by playing computer/simulation/video games.[1]

The most common theory for the cause of simulation sickness is that the illusion of motion created by the virtual world, combined with the absence of motion detected by the inner ear, causes the area postrema in the brain to infer that one is hallucinating and further conclude that the hallucination is due to poison ingestion. The brain responds by inducing nausea and mass vomiting, to clear the supposed toxin.[7] According to this theory, simulation sickness is just another form of motion sickness.

The symptoms are often described as quite similar to that of motion sickness. Some can range from headache, drowsiness, nausea, dizziness, vomiting and sweating. A research done at the University of Minnesota had students play Halo for less than an hour, and found that up to 50 percent felt sick afterwards.[10]

In a study conducted by U.S. Army Research Institute for the Behavioral and Social Sciences in a report published May 1995 titled "Technical Report 1027 - Simulator Sickness in Virtual Environments", out of 742 pilot exposures from 11 military flight simulators, "approximately half of the pilots (334) reported post-effects of some kind: 250 (34%) reported that symptoms dissipated in less than 1 hour, 44 (6%) reported that symptoms lasted longer than 4 hours, and 28 (4%) reported that symptoms lasted longer than 6 hours. There were also 4 (1%) reported cases of spontaneously occurring flashbacks".

A research done at the University of Minnesota had students play Halo for less than an hour, and found that up to 50 percent felt sick afterwards.

这比例还真够大的……

后面那一段数字才恐怖，44％参与研究的军机飞行员，在使用飞行模拟器之后出现了motion sickness

我决定报考飞行员了。*/-91

MGS4跨不跨跟我無關
我重點是跨平台後的畫面對比*/-48

==========================
半條命2完全不能玩，暈死了*/-20

[本帖最后由 allensakura 于 2008-7-14 10:36 编辑]

游戏机最重要的是GPU而不是CPU，PS3本末倒置*/-19

阉割的7900GT也好意思拿出来*/-19 */-19

XBOX360最大的缺点就是三红*/-19

没玩过佳作，就别学人出来喷，回去修练一下再说，谢谢*/-31

拜一个*/-19 */-19 */-19 */-19

RSX用XDR？还嫌XDR的容量够大么。另一方面说：谁认为+turbo cache的6200是198bit的？

標1080P是指支援1080P
我這裡有N片1080P大作等您踢爆*/-48
還有SONY的1080P是FULL HD 1080Ｐ

楼上的，上次我好意给你加了25 HJB。你也不谢我。 最近你投资成为暴发户，我是不是可以连本带利把HJB要回来了。*/-38

我只知....PS3的三國無雙5,比PC版濫多了....當初我為什麼花這麼多錢買PS3...

XO360跟PC已經夠了,外加台WII騙騙女孩~PS3毫無生存空間*/-41

那我現在感謝來得及吧*/-50
多謝多謝多謝*/-24

Uncharted, R&C, MGS4, GT5P，还有10月的LBP。
当然，你不喜欢这些类别的游戏另计

TAA跟2XMSAA能比嗎？
＝＝＝＝＝＝＝＝＝＝＝＝＝
HALO3不這樣的搞法，720P+2XMSAA相信是很容易的
「看起來」也不見得比較差*/-15

[本帖最后由 allensakura 于 2008-7-20 22:33 编辑]

Gears of war是1280x720 no AA。据说第二部也是同样的分辨率。我发现用Epic Unreal engine 3.0的没一个开AA的。 因为这个engine在DX9下没办法开AA。 虽然console因该有解决办法，可是没有人尝试。

http://forum.beyond3d.com/showthread.php?p=1113342#post1113342

这么对比的话那个console里游戏开AA一目了然。 咱们实事求是好不好。

游戏好玩不好玩是一个，效果是另外一个。 我没说MGS4不好玩，我说MGS4美工好没错吧。

我只是回应。。。。

彩虹六号用的是UE3