HD4850 vs HD4870

I'm stretching the budget for it a bit for it. I mean, it's the double of the price of my CPU. XD But seriously, it's using a Vapor-X system, so I -will- try to overclock it. I'm not entirely sure how much extra performance I'll be able to extract from it, but it has all 16 ROPs up and running so every MHz will count. The RAM part, I pondered a -lot- about that. I mean, what I'm getting is the 1GB version, but in the end the 4850 is GDDR3. It has an apparently rated 64Gb/s transfer rate against the 4870's GDDR5 with a near 115Gb/s. I don't understand that deeply a graphical card to know how much the RAM transfer speed can cause bottlenecking. But, PSU aside, it was a -60- Euros difference. That was a bit harsh, even if the 4870 had 2GB RAM. Machine still has to be assembled, but, I'll be sure to put in some values later.

Well, it's already too late since I already ordered the 4850 and all, but I actually got into the same dilemma when a friend of mine asked me for help picking a card. Being a good bit weaker(the 9600GT that is) it detracted from its value, however, it'd be a good replacement for my current computer since it would mean I didn't need to buy a new PSU at all, but since I'm assembling a new computer altogether the difference isn't much. Thamk you for the reply at least

The latest model hold true in my opinion, if you create a new model then it should be better than the last one, it will always correct the previous problem of the older design. It is still a misconception, since the unit is self certified, its manufacturer can claim that it can double or more than it can actually provide, although it can be safe in terms of overloading, larger unit is often less efficient at power loads, meaning under 20% of its total capacity, regardless of its design, PSU of 6 years ago or PSU of today.

Well, VGA wise, you can look at the 4770 and the inferior 4830. It's a later model number, you'd think it's better, but it's not. The only thing the 4830 has to show is a 256bit bandwidth for the RAM, but it uses GDDR3 and the actual bandwidth value isn't too far away from one model to the other. The GPU also runs slower and there's less a ROP block. Thus, if I just look at the model number, I can come out cheated. As to the power supply, I'm not analyzing lies here, I'm talking about actual physics. If a power supply claims to have 1000W I'll assume we are discussing that there is a total 1000 watt power capacity in there, and I'm not just assuming it's a lie from the manufacturer. Can it happen? Yes. Is it always necessarily a lie? No. The singular reason why an older 1000W PSU is useless these days it's because they were not designed for the ATX 2.2 specifications. They still have 1000W in there, but the problem is, only 300~360W are oriented to the 12V rail, the rest being for the 3V and 5V. Who needs 400Ws+ of 5V power? Current ones, under the ATX 2.2 specifications have the power shifted towards the 12V rail. For example, my PSU is 520W and has about 22amps on the 12V rail, whereas a ATX 2.2 intended PSU with a 550W power rating has over 35 amps meant to the 12v line, of course, this makes it skimp a bit on the other rails. As to actual power consumption in term of wattage, the 4850 reads a maximum consumption (under load that is) of 251 watts. Now, that's probably one of the components that individually will chew out the most power out of a PSU, but on a 450W PSU in total that would leave us only with more 200W to go to feed everything else.. CPU, HDDs... so their advisory of 400W as a minimum may be playing things a bit on the edge. But remember, this is only the normal 4850 too. There's the 4870, 4890, plus the twin GPU version of the 4870.

The higher number isn't -always- better, I assure you that much. At least, this holds exceptionally true to the ATI cards because of the way they make the leaps in technology and the way they name the models. Although, the doubt isn't between if the 4870 is better than the 4850 or not. The improvement is there, even if not tremendous (save RAM). As to the effect on games, these days it's always noticeable. There's really not half as many issues as before when card X did Z effect, but card Y didn't. So, more processing power, more frames it can render, period. About all that matters (Save nVidia's PhysX). PSU wise, it's not -necessarily- a misconception, but the problem is on the lines of what was ... 6 years ago and what is now. Back then, a 700W PSU had lots of amps on the 5V rail or it even had two separate rails. These days most of the amps is turned to the 12V rail(s) especially because of VGAs. Still, the greatest concern were the amps. I mean, the PSU on this computer is 520W, but the 12V rail amps just weren't enough for the VGA and the rest of the system.